This seminar presents issues associated with poor water quality and how to mitigate these risks from design stage through to commissioning and operation. By watching this video, engineers can learn industry best practices that lead to longer lifespan of plant room equipment, reduced carbon footprint of space and operation, increased efficiency of systems and reduced energy operating expenses.
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Good evening my name is Steven pets and I’m chair of home county Southeast and just before I introduce our presenter this evening have just a few announcements to make first of all thank you for taking the time to attend this evening and thanks to Laura from regions executive at balum providing all the
Much needed technical support for this meeting to go ahead and just really a reminder that siy regions are in place to support the charitable objectives of the institution encourage intellectual welfare of members and improve the standard of Building Services engineering uh among not only our profession but Society in general and
That’s carried out by organizing periodic meetings seminars and cpds as as we’re presenting tonight other activities related to the theme of the built environment so if you have ideas for future meetings or other activities please uh put them in the chat box and we’ll organize that in the coming year
So a couple of housekeeping points you could have your cameras turned off and your audio mute this will help transmission and if you have questions please put them in the chat box and at the end of the presentation I’ll read the questions the speaker and ask the speaker to respond so tonight’s seminar
Is on hydronic closed loop system water and our presenter is Darren Wilkinson who’s the managing director of vexo international so thank you Darren for agreeing to present to us evening over to you thank you thank you for having me and thanks thank you to everybody for
Joining uh this evening uh you know in your own personal time um okay so yeah just very quickly a bit about me uh yeah managing director at vexo started my career originally in the Marine engineering world in the Royal Navy many many years ago and um subsequently
Somehow got into aut treatment uh when I came out of the Navy many years ago so uh that’s that um but um straight into this uh into the presentation then the CPD uh we’re going to be talking uh over three different modules essentially the first one is types of closed loop
Systems that are relevant to the CPD it’s really important because there are different ways to tackle water treatment water quality depending on the type of system we’re going to look at uh in the other modules as well we look at design considerations that are very very
Important uh if you want to have a clean and well commissioned system for the rest of its life credible to grave uh and then module 3 has really just taken us through kind of competence or competency it’s always a bit of a a bit of a bandwidth long bandwidth on that
Piece in terms of what what is competent but um certainly direct you to guides and uh Industries and uh and so on so that that’s really what we’re going to run through so to kick things off types of closed circuit systems uh this is relevant to your Chiller systems your
Condenser systems and your heating typical heating central heating SL you know lphw water in a commercial building um you could even and say the same applies ultimately in in the domestic dwelling and what we’re not going to be covering really is and and and taking a notice within this zbd uh applying to
You know medium pressure hot water or steam raising plant so what is a hydronic closed loop system without making you suck too many eggs uh a circulatory pressurized heat transfer pip work Loop uh that does not normally require regular makeup so it’s essentially a sealed system doesn’t have
To just be a heating necessarily you could find this in industrial if you’re working on projects in industrial and you have some form of heat transfer you’ve got a a pressurized Loop um heat transfer system the materials generally made up of various mixed Metals rubber Plastics and fiber washers U no systems
Really the same uh Heating and Cooling Source can vary particularly now as we’re we’re moving to Net Zero um but typically you can lose you know roundabout or up to 10% of the system volume over course of a year regardless that it’s a sealed system uh some can
Lose much more so there’s plenty of age systems out there at universities and hospitals that lose a lot more water uh we were working with a client that was losing losing 30 ton of water a day uh at one point uh and it’s when you have these water losses or this makeup of
Water you bring in more problems unless you’re of course doing something about it so I always say if you take a heating system uh without sounding too dramatic but think of it as a chemical reactor uh so we’ve got different types of metals we’ve got water an electrolyte we’ve got
Oxygen uh and particularly in a heating system as we heat heat water up chemical reaction rates increase so I always sort of say to get the picture in the head think of it as a chemical reactor so we need to consider that thermal transfer fluid that water that we’re pushing and
Pumping around as it were um what are we going to do about it without uh you know so we don’t have that impact in the uh the actual overall system due to poor water quality um so in terms of uh the objectives of water water treatment sorry actually I just realized I should
Have I should have said something else there that’s a heating system as a chemical reactor so a chill water system consider it an incubator so running a much lower temperatures we’re going to see more issues associated with bacteria and um certainly you know bacteria indu corrosion so both both types of systems
Heating or cooling need to be considered so the objective really is to make sure we maintain the system in a clean condition so when we Design Systems we design for efficiency more so now than ever um we want to be able to assist the maintenance of that system and that
Efficiency and we want to prolong the system life as much as we can when we look at capex budgets particularly you know um embodied carbon and we’re doing calculations now digital twins of buildings understanding Cradle to grave well actually if we don’t take care of that water quality that lifeblood within
The system uh that’s going to throw those calculations out uh and and overall as well at project level and trying to hand over we want to un we want to avoid conflict and misunderstanding so lots can go wrong if we don’t get it right uh and that generally manifests is you know as
Things breaking down much sooner than they should do you know your energy bills are scooting up again it’s not as per the model um you can have a huge amount of operational issues uh customers falling out uh and so on so there’s I mean there’s various LIF lists
There but certainly as well if you do get leaks you’re looking at building fabric damage as well um and unfortunately litigation which is quite common believe it or not um due to poor water quality so the objectives of of the water treatment specification when you specify uh water treatment water quality
Typically it’s easy to do a cut and paste and a lot of people I know refer to the bizer guides um so depending on the size of the system I mean it comes at a cost but it if you if you’re quoting the biz guides generally you
Know you won’t fall short if the contractor is working to the standards um and there’s a lot of good information in the bis guide in terms of the types of you know forms of contract uh your method statements considerations there various quality assurance um making sure as well there there’s plenty of due
Diligence prior to the project starting always good to involve a water treatment specialist at the design stage because they can come in and advise you on the design in terms of allowances for getting the system clean essentially if you don’t have that it’s going to be very challenging thereafter once the
System’s handed over if you’ve not actually fully cleaned and removed any foreign objects or construction deposits and corrosion Etc so um first of all it’s about setting out the road map of how you want to deliver your project and considering have you got all of that in
Place in you know terms and pertaining to water treatment um in terms of basics of the problems we get keeping it simple uh scale if we’re in a hard water area we see corrosion occurring in our new nice new equipment we can see microbiological growth sometimes looks like a slime or a
SL slimy sludge that comes from the system and then we can have fowling and sludge which is generally composition of all the above uh we can also have sometimes um systems whereby um you know things are deliberately put into those systems whether it be and it’s happened pingpong
Balls cans of coke nuts and bolts uh I even came across a site where there was a hard hat pair of boot and overalls in in a huge condenser strainer so you never know what you’re can to find so having the design with the right sort of flushing loops and uh requirements um
For the cleaning specialist are really key and this is kind of what it looks like uh if it goes wrong and I say if it goes wrong there is actually one photograph there that that is actually a good photograph believe it or not to see
And that’s the top left one uh in the top left is a uh A system that has you know had good flushing bypasses fan calls are all bypassed uh and the contract got those velocities to bizer standards around the system and removed all of that corrosion debris um and pulled it
Out of the strainer as you can see there so that heavier much heavier uh detrus was managed to be moved and out of the system so again if we don’t have the right design we’re not going to remove that and then what does that mean in the
In the long term we’re going to be looking at unfortunately the other photographs that you’re looking at so whether it’s reducing the flow rate affecting the delta T uh complete blockages of pipe work plate heat exchanges uh and play heat exchang as the might add you know where we’re
Seeing huge amount of hu units now installed or uh a lot of retrofit involves typically see a lot of design with plate heat exchanges to protect the new equipment from say for example an old school um heating system but it doesn’t help the client the building owner if that secondary side of the
Plate heat exchanger becomes fouled uh you know they’re not going to be getting the heat delivered that they need and particularly as we move to uh much um you know zeroc Carbon techn techologies so keeping perspective I always like to say it’s a bit like a car
You know if you’ve got a car we understand if we don’t change the oil as we should we don’t get it serviced as we should it’s simply not we’re not going to get the miles uh or the life cycle out the engine and we’re not probably
Not going to get the miles per gallon per gallon from the vehicle either so it’s a bit like that with our heating systems we design for efficiency but if we have dirty filthy water running around your system uh you’ve not taken a care of it you know chemically and microbiologically
Uh you can have fall into problems so we mentioned uh or I mentioned should I say um the various uh you know grenade example one starting with scale so scale in hardw areas you know it’s a mineral that is in solution um it comes through from when we have
Rain through the Bedrock it picks up these minerals um and ultimately ends up in our water that comes through our tap so if we have no pre-treatment prior to going into the Clos system and we’re in a hard water area we are going to introduce scale now ironically scale can
Actually act as a bit of an inhibitor it sort of somewhat passivates but unfortunately it opens up other problems one is obviously energy loss because we start getting scale buildup uh on the point of heat exchange particularly uh but that scale will break off powder off almost and uh microscopically it will be
Very abrasive to the pipe work runs and the you know other bits of equipment that are on the system so we can either control it through ion exchange I.E water softeners um or we can add an inhibitor so an inhibitor will prevent that scale from precipitating out of solution under
Temperature so depending on where you are where the project is uh more to that matter whether it’s in the UK or the Republic of Ireland uh depending on your project you’ll take a look at that and you should consider do we need any kind of pre-treatment for this system should
We have leaks should nobody be adding any kind of inhibitor or there is no pre-treatment at all it’s just something to be aware of so that’s scale and then we have corrosion now corrosion very broad term really but there are very various types of corrosion um but a point to note is
We Can’t Stop corrosion if someone says oh we can stop it you can’t stop corrosion it can only be slowed and controlled um so the more we can do to keep the system clean chemically stable free from bacteria uh we we’re going to certainly look to hit that 25 year plus
That we should expect from from the system unfortunately now price in the market new technologies p NW work systems uh some of them are a lot less forgiving they’re much you know much of the older much thicker steel systems that were installed you know 50 years ago where some systems are still
Operating but but you know metal essentially corrosion it’s the metal wanting to go back to its natural state so what makes it more corrosive well first of all it’s oxygen so we want to keep the oxygen out of a closed loop system which is why you’ll see uh
Depending on the system parameters a dirt and air separator or a vacuum degasser uh or possibly something I’ll get on to is is the vdi standard where they use um a sacrificial anode so there are various ways to we can manage oxygen but point being is we want to make sure once that
System’s filled we want to get all the oxygen out the system as best we can low PH so pH uh running from a number of one being very acidic to 14 being very alkaline or costic pH neutral is deemed as seven well it’s actually 7.2 but
That’s kind of in the middle so there are other things we need to consider low PH so sub I would say if I’m honest sub seven but only less than sub 6.7 um we’re going to start seeing increased corrosion rates within the system so if you’ve got a lot of
Corrosion one of the tests amongst many is pH The Specialist would do higher temperatures again chemical reactions uh or corrosion rates and chemical reaction rates increase with temperature so it’s typically why you’ll see a lot more this magnetite uh in a heating than you would on a chill water system we can have
Aggressive ions within the water um for example chloride um so we can see that that can create you know stress corrosion cracking for example on stainless steel if it’s highly concentrated uh certainly locally um we can see failure and then another corrosive uh matter we need to consider
Is Deb sludge and biofilm it’s it’s like shock blasting inside of the pipe work so if you are using corrosion inhibitor uh it’ll be it’ll struggle basically to lay down its film so you’ve got to maintain a good level of clean water at the same time and being free of suspended solid
Um so if we want to control corrosion we need to basically interfere with with the with the oxygen that’s the first and foremost part and ultimately be sub you know 0.2 PPM of oxygen within a system to to have control of that we can try and stop the oxygen getting to the metal
Which is where Inhibitors can can really play their part or we stop the metal going into Solution that’s where you know your Inhibitors or your sacrificial anodes for that matter can can play their part so there are there are things we can do there are technologies that we can
Apply um so galvanic corrosion on on the casee of corrosion different types of corrosion galvanic corrosion this is very much when you have dissimilar metals and the further apart that they are on the galvanic series uh you can expect to see a higher rate of uh chemical reaction taking Point At You
Know that location where the two metals meet um but for it to happen you need to have water or an electrolyte passing through so you won’t have a same issue if you imagine a flange connection pip bolts on the outside there’s no water passing over you’re not it’s not such an
Issue but it won’t an issue but certainly on the inside when we’re passing that water through two different Metals meet so we need to make sure they’re not in electrical contact with each other so it’s very much understanding the types the right types of joints to use and certainly plenty of
PTFE or Teflon tape um but of course one thing we can’t control is if any deposits laid down on the inside of the pipe work of course that’s a bit like a a wiring or you know imagine a contact being made across um a piece of Electrical uh equipment um suddenly
We’re going to see localized corrosion taking place so again a lot of Engineers when the designing systems you typically find the metals and if you take a look at the ganic series there you’ll see a lot of the metals are very close together for the most part uh on that galvanic uh
Table we have something called uniform corrosion uh uniform corrosion is what it says on the tin it’s pretty much you know as you see the pipe work there on the top right picture a lot of the surface there is what we would call uniform corrosion um and that’s quite
Easy to predict and to to check using corrosion coupons uh there are methods as well that we can we can test that um remotely you know technologies that are out there as well and then there’s aluminium corrosion so a huge amount of commercial boilers that are specified
And I know we are moving to heat pump and we we should be moving to heat pumps or other Technologies certainly um but again aluminium is a great metal in terms of you know in terms of ability to transfer energy transfer heat most efficiently unfortunately in a water
Treatment uh situation or water quality situation aluminium is is very sensitive to pH in particular and a lot of common corrosion Inhibitors by water treatment companies that are used are generally alkaline based and aluminum requires neutral pH uh treatment it needs to be maintained below 8.5 anything over that
We’re going to start seeing degradation of the uh the actual aluminium uh and you can see boiler failures typically as well quite common so we need to try and reduce the oxygen uh and that will help reduce the erion rate so um there is a correlation between dissolved oxygen and
What we’d call free air uh and quite frankly the difference is if you imagine uh Henry’s law which is if you had a a fizzy two L 2 lit bottle of carbonated fizzy drink um within the bottle there’s a there’s a pressure a standing pressure which is above atmospheric inside that
Bottle so that pushes a lot of any gases are in solution you can’t see them until of course you unscrew the lid and then you start to equalize to atmospheric we reduce the pressure inside and those dissolved gases come out we can eject them obviously in a closed loop system
Not so straightforward um so the only way to do that is either through pressure step degassing where we actually put it through a a volume in a cylinder a volume of water at a time and we reduce the temperature sorry we reduce the pressure in that vessel in a
Moment in time which reduces dissolve uh gases that we can then send that water back in the system but that does take time you’re only doing so much but you know over a long period um heating systems if I’m honest um you know you probably find a lot of that oxygen will
Be used up in in with the temperature in any case by the time the gas is looking to any work but I certainly see you know the benefits on chill Water Systems in particular and you know cooling cooling water systems highly valuable I would say because the other way that we
Removed uh dissolved gases is through temperature as I said if temperature increases they naturally want to come out and they’ll come into sort of that free air state and they’ll come out of an automatic air vent so um there is a correlation if you remove more of the
Free air you will you will pull out some uh not all but some of the dissolved oxygen as well uh pitting and under deposit corrosion uh can be very similar in terms of um how they look but pit and corrosion is if you have a dirty pipe
Work uh you’re laying in you’re laying down inhibitor and you’ve got inconsistent film um you have this if you like um demarcation I guess where between one side is anodic and the other is cathodic cu one side is being protected by inhibitor the other side is not and unfortunately that’s where we
Start seeing localized pitting corrosion um on the surface at the same time we have under deposit corrosion so as you can see in the bottom left picture deposits settle out in a lowf flow area or as the the flow rates um you know encourage things to settle out like you
See there on the radiator and what happens is we have below the um below the deposits we have um a lot less free oxygen available and above the deposits there’s a higher level of oxygen and so that creates electrochemical reaction um that drives corrosion locally um underneath uh hence under under deposit
Corrosion so again it’s important that we don’t from the get-go we do not have any deposits that would like to settle out in the system so we got to keep the system again chemically treated if required or certainly chemically balanced and and um and prevent any suspended solids really from C
Ulating um some bacteria particularly an anerobic bacteria sulfate reducing bacteria they can quite easily Thrive underneath those deposits and as part of their byproduct even ion bacteria part of their byproduct they will actually produce acids and those acids can then cause pin holing so if you if you have
Horizontal pipe work and you start seeing pin holing chances are uh you’ve had deposits lay down and it’s generally flow flow rate related we have crevice corrosion so again it’s it’s this sort of um Rel relationship between the amount of oxygen in one location to the
Other um if we have a crevice it’s a bit of a dead leg for example um we’re going to see again a a drive in the chemical reaction at that location so the photograph to my left or to your left as you look at it you know there a flange
And you can see the damage that’s occurred there um and it would it would appear that really when the flange was bolted together it wasn’t bolted together you know opposingly when you’re tightening up the nuts a bit like putting a car tire on otherwise you
Won’t get a nice firm flush seal and you allow for this crevice to occur and the photograph on the right is actually some thin wall press fit uh carbon steel pipe work which I I see nothing wrong with the if I’m if I’m honest the installation um I think the install has
Buttered it up nicely crimped it nicely but um unfortunately there’s a there’s a gap there’s a crevice and so thin wall pipe work uh it’s quite unforgiving if you don’t get your water quality right well particularly carbon still another form of corrosion is erosion corrosion so if we um if the
Flow rates are too high I know it sounds like you’re asking for the dreambow here they can’t be too too too low and they can’t be too high got to be just right like the Three Bears story but you do have to have your flow rates right if
You do not like I say you’ll encourage deposition but at the same time uh if you have too much you you could start looking at erosion corrosion as well particularly on the softer Metals so the picture on the top left is some copper you can see that scouring that’s
Occurred um and particularly as well erosion corrosion if you’ve got deposits once again it’s like shot blasting you’re going to have pump seals failing so it’s normally the first giveaway if you’re getting pump seal leaks chances are you’ve got a water quality issue uh rather than a pump uh SEAL issue
Generally pump manufacturers don’t make bad pump seals so uh and then cavitation is another form of corrosion so uh rapid formation of or collapse of vapor bubbles that are Chang in fluid pressure uh adjacent to the actual metal surface so we can see this you know typically
You know pump impellers for example if maybe they’re not quite balanced correctly or the the flow rate or the the demand into the pump isn’t being met um you can hear this uh typically you can hear cavitation as well pumps in particular this kind of rattling like
They got nail Bag of Nails that are rattling around inside and that can be extremely damaging so that is another form and then there’s stress corrosion cracking um doesn’t come up as often uh as amongst the other issues of corrosion um but typically in in in our industry
You’d see it mostly on chill Water Systems um rather like the fire triangle to have a fire you need to have you know a fuel a fuel source you need to have um heat and you need to have oxygen and if you take one of those away you you won’t
Have a fire stress grage can cracken is rather similar you need a tensile stress so we’ve got a hydraulic um you know close loop system Under Pressure we’ve got connections that have been threaded and you know Under Pressure where those joints have been made we need a
Susceptible material so in the case of a chill water system it will be say chill as I say chill water typically um you may have had a bacterial issue and as a byproduct they create ammonia uh and unfortunately that ammonia becomes the cor you know part of the corrosive
Environment for the system so the susceptible material in this case would be a brass fitting um don’t see it as often and certainly see it a lot less than we used to nowadays CU there’s dzr brass but there was a period where Engineers would specify bronze on CH
Water just to be completely you know covered I suppose rather than a brass and if you have a poor quality brass you could have failures whereas now you know there is the the standard for brass to be you know desync ification resistant um so much higher quality and a lot less
Um Alloys in there like zinc for example that would that would normally um be stripped out by the ammonia leaving porous copper uh I think this is going to start showing its head more so now we move to much lower operation in temperatures but this is another form of corrosion called
Microbiological influence corrosion mic so essentially we can have bacteria that um if you imagine the fresh water that makes up to the closed loop system you know pip work can be sitting there for some time um before there’s a demand on the system that says topping up and
And in that time Main’s water will have very low level of to Total viable count have low level of bacteria in the water typically they like to think certainly not uh any pathogenic uh concerns but certainly low levels of bacteria in the water and of course if it sits there
Idle and it’s got the right temperature it’s going to proliferate and you’re going to have bacteria so every time the system makes up you run the risk of giving it a a flu almost you know um you giving it a dose of this bacteria once it’s into the system under you know
Stagnant conditions it will multiply so the bacteria itself will um create a bofilm eventually um this slimy looking goo which you can see on the picture on the right hand side that’s actually a filter cartridge filter under there um and it’s literally the layer of this slime is
Just peeled off this was a US military base in in Upstate New York uh they were using a ground Source heat pump system having all kinds of problems um so yeah and and the other thing they produce you know acids and and extremely you know you get smells as
Well you typically know on on a cooling system in particular and you get this horrible smell so um that that’s a concern localized corrosion because of that also indirect will be the breakdown of any bi um any Inhibitors nitrite um bacteria just noted in typo there actually embarrassing uh nitrite
Reducing bacteria nrbs are uh are a bacteria that will actually use the the inhibitor the nitrite inhibitor as a food source so whilst nitrate is a great inhibitor it’s an alkaline product so you know be careful where you use that unless it’s a particular blend um it
Will feed bacteria um again give given an anecdotical example I was walking around a project I said how’s the water quality I was told no major issues apart from October we turn things on we get a few pump seal failures and a few radiators leaking um so I explained well
You know that can be avoided and I said anything else he said oh yeah we we top up loads of nitrite in the uh you know as we look to shut down the heating make sure it’s got plenty of inhibitor but every October we fire it up it’s all
Gone so turns out was bio you know biofilm and bacteria so in terms of glycol concentration as we’re looking at you know ground Source heat pump systems and other types of uh renewable systems that’ll you know require some level of antifreeze some some level of glycol we’ve also got to consider that uh
Typically the industry considers anything above 25% uh volume by volume or dosed uh glyco antifreeze in a system it’s biostatic you shouldn’t expect to see any issues really but anything below that as you can see from this graph that you start to run the risk that you’re
Going to start feeding the bacteria so rather than they they can’t flourish they actually can flourish as the lower the levels of concentration you go and unfortunately not only do they consume your glycol they actually produce glycolic acid so you can end up with gasing in the system acidic pH uh and a
World of problems essentially so if you are looking at a system to add glycol I’d certainly uh you know the industry generally recommends make sure it’s at 25% so module two um so we’ve got we’ve got given you an understanding in terms of corrosion the types of corrosion and where it can
Go wrong so now we need to think about design considerations for a clean and efficient system and there is quite a lot here from uh you know bizri that I’m referring to but I do talk about the video a little bit later on um not as much depth I’ll be completely honest
With you that’s still an area that uh us at Vex are reviewing uh including the Technologies we’re working with a German manufacturer in that technology as well but for the moment uh bizri let’s you know focusing on Biza so Biza is a great Tool uh when you’re looking to uh put
Something in your specifications to ensure that you know the contractor is is is quoting correctly so um but it does talk about the front end the need for early engagement and I really do stress that if you can engage with a water treatment specialist early on and
Say Here’s my schematics this is what we’re looking to do um these are some of the flow rates we’re looking at for the design um you know is there anything you advice that we should consider I I do recommend that because there’s various things about design features uh as it
Says they’re permanent or temporary it may be that you know there needs to be some some valves arranged for a temporary hose to be installed because you’re connecting to an existing Chiller um and maybe you don’t want to leave a hard pipe temporary bypass so just something uh sorry a hard pipe bypass
You want to use something temporary um which things need to be bypassed what types of methods of cleaning are appropriate for the system and sometimes weather cleaning is is important to be successful uh you know you might have a small system and it’s all stainless still pipe work and it’s
You know do we really need to go through that so engage early on certainly with a specialist would be my advice and then we have the different sort of stages of the clean to consider so when the system’s first filled generally it’s recommended it’s filled with treated water you rather than
Filling with raw water and you don’t want to fill a system and certainly drain it once you filled it actually makes things a lot worse um but typically the approach the water treatment company will take is dynamic flushing so this is where they would take terminal units put them into a
Bypass situation before you even run those pumps uh once you’ve got those pumps ran and everything’s in bypassed they would then look to dynamically flush which means that they look at the velocity so they would plug on a you a monometer and they would check that they’re achieving the flow rates across
The um horizontal Branch branches of the PIP work so anything above or 5 millim up to 5 mm inze will be moved and you can hear this on these projects when this is happening you can hear things dinker like your tapping sound almost as a little nut or
A washer in fact I’ve you know come across you can hear it moving its way around and it ends up in the strainer so all that construction debris or anything that might have been put in there any kind of um sabotage even you want to
Know that you know are you going to have a blockage or or is that system going to operate so good flushing is really really key good velocity is so key uh typically buide washes um for systems at risk from bacteria if you’ve got terminal units that been wet tested or
Even chillers that are wet tested it’s really important question to ask the uh OEM because if it’s been wet tested and I found a chiller once many years ago that um before we opened it to the main system this is before we were in the world of making it a regular thing
Bioside washing we found about 4 inches of biofilm inside the chill where had been wet tested and sat on a dock somewhere for probably months um but so a bioside is rather like an antibiotic if you you consider the system could have bi you know slime in those terminal
Units let’s say and bacteria flush the system first at velocity add your bioside and what typically happens is the contractor all then um back wash forward wash into the coils get the air out of the coil and leave it then with bioside then they close those coils off
Go back to bypass mode and then whilst the rest of the clean’s happening you know that you’ve essentially given those those units a shot of bacteria sorry an antibiotic um then when you think about cleaning any surface oxides different types of cleaners are available uh particularly if you’ve got steel uh they
Run the cleaning agent then around the system for a period of time um and then finally they need to come and flush that um need to consider effin disposal as well with a you know within the specification can you dispose or do you need to bring you know offsite uh
Bowsers but once that cleaning agent the buight is flushed from the system then they would add the inhibitor in a bi side typically uh and then bring online each of those fan calls by back flushing at the same time any water loss is made up with inhibitor and
Biosite so we want to design for water quality avoid any dead legs make sure we’ve got line size flashing bypasses I’ve I’ve seen systems with 6-in District Network pipe work and a 2-in bypass and there’s absolutely no way we’re ever going to move you know the contractor is ever going to move
Anything sitting in that pipe work through a 2-in bypass you you have to have line siiz bypasses realistically um particularly if somebody’s got to bring in temporary pumps um treatment starts before filling so again make sure the you know what’s the water quality typically add a bide inhibitor where
Your first feel uh there are much lower you know hazardous risk additives that can be added at that stage uh make sure the flow rates do not encourage deposition or erosion so typically we certainly don’t want to be above sorry we don’t we want to be above 0.5 m/
Second um and we don’t want to be above the sibsy guide in terms of Maximum flow rates per pipe diameter uh make sure we’ve got the right correct pressure vessel um really important see many system failures and then actually it turns out they haven’t been the the vessels themselves haven’t
Been sized correctly and of course when the system’s operating it starts drawing in oxygen strainers and dirt and air separators uh typically uh filtration at five Micron and with a form of an alarm so you know whether it’s one or all of those Technologies having that sort of Technology strainers catch your bricks
To you know to use a phrase um they will catch the big heavy stuff in the first pass that you need your strainers dirt air separators catch the kind of little much granular stuff that will drop out very quickly um and then finally you’re left with this very fine
Sand which is where you need your filtration as well but you certainly need to know if these things need changing I an alarm system uh if you are using de gasses please make sure obviously check with the manufacturer they are correctly sized for your system volume else you really won’t be
Achieving much dosing pots are recommended on systems below 1500 L um of a way of adding chem chemicals unless of course you go down the vdi route uh plas plastic pip work this was a major problem years ago not so much now people have caught on to it but a lot of
Plastic pipe work was being installed that was not um it didn’t have an oxygen barrier so it would uh wouldn’t let water out the pipe work but it would it would almost breathe it would let oxygen in um and the ministry of Defense had a project years ago that they they were
Changing radiators after three months cost Millions um because they create this huge chemical reactor uh we do recommend dirt Pockets at the bottom of RIS so anything heavy particularly on the precom cleaning you can grab it without it causing damage around the system plenty of vents sampling points
Um and if you do if you’re working on a shell and core you do have a fit out um you know can have a lot of fit outs make sure you’ve got the right fit out bypasses and isolation so I.E if somebody comes onto that floor tenant
You can isolate the floor but open the bypass make sure there’s a bypass installed and certainly as close to the Riser as you can think about flushing valves for the uh the installers on the fit outs as well as well as well as the main system uh and making sure with you
Know there’s metering stations at the various branches to prove the uh flushing velocities achieved basically so lots there but essentially the message is design the whole program really accordingly going back to bizri they do provide uh information in terms of what You’ expect your flushing contractor to achieve in terms of
Velocity dependent on pipe size so again if you’re looking at as you Design Systems you’re looking at what is your flow rate you’re looking to achieve at design just take a look and maybe you know quick look at the bizra guide and say if if we wanted to could we get up
To that because there are systems that have been ultra low flow almost um that just impossible to clean as well so again all of this is available in the bizer guide uh as well as um information in terms of sampling there is actually a British standard um BS
8593 that provides a lot of information on sampling as well um just something we managed to get in here and siy let us have that in there bit cheeky but uh something we’ve launched recently of EXO uh through BSS as a boss product is actually an inline strainer
But it’s got a dry pocket magnet so um idea being is anything uh that would normally pass through the mesh um we can we can grab it certainly anything you know that’ll be attracted to a magnet which in most cases not just magnetite but that magnetite will be covered in
Some form of a biofilm and maybe some hard scale so actually the more we can do to prevent that uh strainer mesh from blocking uh it’s going to mean greater efficiency on our pumps and not working so hard and actually less maintenance and yeah to be honest how often do
Strainers get cleaned as well I think um so there are Technologies like ours or others there are other magnetic strainers I should add that um available out there as well um so there are Technologies to consider that that can kind of Safeguard let’s say circulation is so key for systems I can’t stress
That enough uh naturally people would with assume well hang on it’s you know it’s the summer or it’s this spring and summer we don’t need the heating running at the school now we’re just going to turn everything off and it sits idle but actually just like a car you know you
Were going to go off traveling for 6 months you wouldn’t want to leave your car on the drive with the battery connected and and not moving the car it’s always good to have somebody maybe a neighbor or somebody you trust you ask them maybe to run the car around for you
Um keep things moving uh just like the human body if we sit for too long water quality um there ISU hugely impacted basic if you uh allow it just to sit idle um particularly if you’re using Inhibitors they like to have circulation so B recommend 1 hour and every 24 hours
Circulate that water you know actuate valves keep things moving don’t let things sort of seize up um and you’ll certainly increase the opportunity for things to settle as well biocides going back to as I said about bacteria um we we want to add a bioside to a system
Typically to deal with the the uh the buildup of a biofilm in the first place so we don’t want bacteria to flourish within our system um and obviously we don’t want to lose any of our inhibitor as well so if your contractor is adding a bio biocide like
An antibiotic it’s also very important that it gets added with a biod dispersant so bioside will will kill bacteria but it’s got to get to it so if it’s if it’s protected Bel beneath this biofilm what will happen is um well nothing will happen in fact because the
Uh the chemical cannot get there to to attack this bacteria so adding with a biod dispersement will break up that jelly like substance and and allow it to then kill the bacteria so if you are using Inhibitors and again I’m just leaning more towards the bisri approach um we just need to
Make sure that it’s effective so for it to be effective we need a clean clean system so we can get to the full metal surface uh surface of the system um and we want it to be free of pip works you know scale uh biofilm and so on
Otherwise we’re simply not going to get the level of protection and and really importantly we want to make sure we’re maintaining the right level of inhibitor uh as well so um you know I do come across some sites where you know the water treatment contractor said oh there’s not enough inhibitor in this
System but they hadn’t consulted the manufacturer’s um product data sheets different manufacturers will require different dose rates let’s say or or certain chemical composition uh items that you’re looking to analyze through a test kit but keeping the right level of inhibitor is really really key if we are using an antifreeze um again
Used in chill water typically two types of antifreeze there are mono that’s monoethylene glyco this is the poisonous uh the poisonous antifer there actually been cases even a movie made once about this where a lady was slowly poisoning her husband and they couldn’t work out what was wrong with him she kept
Bringing him soup to bed um and was adding a very small drop of ethylene glycol so it is very toxic and then there’s monopropylene which is suitable for food use um we would recommend now it comes at a cost but we would always recommend if you can go for propylene
Glycol and specify propylene glycol in a world where you know we’re getting better with our ESG agenda um you know we are thinking about the environment a lot more and so we should think of the risks if you specify or allow someone to use ethylene glyco in a you know for
Example a ground Source heat heat pump you know uh array what if there’s a leak what if the contractor makes a mistake or there’s a spillage that is going to end up in the aquifer that’s our drinking water so I you know if you are considering how can we be greener of our
Our projects I do recommend comes at a slight extra cost but it’s well worth it it it’s much safer overall um this isn’t necessarily my field of specialty um specialism but it’s something I wanted to add in there and I I consulted with somebody at TARTA still about this and I think the
Industry is somewhat now finally changing but um excuse me carbon steel whether it’s hot or cold Form application so um in a nutshell um when you’re specifying you know the materials the systems designed for if you are specifying carbon steel there is a British and Ann standard um in terms
Of its application so just know that if you are using uh cold form which comes much let’s say more competitively than the hot form um it also carries risk if you don’t apply it correctly uh to the right sorts of system so certainly on Cold Water Systems um but even on on um
On hot water systems and and even on Cold Water Systems there can be pH issues potentially um so again if we’re looking to to to model a building we’re obviously basing that on life cycle of equipment that goes in the building so if we don’t specify correctly we could
See failures and obviously if we use if we have a failure in a building of main pipe work then that that’s going to impact more than just the uh the heating or the you know heat but in this case the heating system it’s going to be all the building fabric damage that goes
With that so uh yeah ultimately go for hot form if you’re using you know Clos Loop heating cooling systems uh pretty much just what I’ve covered there and then as I’m just sort of getting the end quickly get to the end of module two you be glad module 3
Won’t take too long um as we as as we approach uh the controls philosophy or as we approach sorry the module 2 the end of module 2 control philosophy is also really key only about 20% of commercial buildings have BMS um the other 80% typically have uh you know fixed logic
Control as manufacturers controls um pretty much it’s a Time Clock essentially so to um something to consider when you you’re looking at the controls Philosophy for a closed loop system is understanding again as I’ve said where you have stagnant conditions for example um keep water moving moving
So whatever you can do in the controls piece to mitigate bacterial growth you know maintain good levels of of treatment around the system consider all of those things there um as part of you know the the design um uh philosophy control philosophy so yeah circulation think about the pressure in the system uh
Think about the incoming water quality flow rates uh treatment of any sides potentially or you can use thermal pasteurization sometimes depending on the system certainly think about your water sampling onsite and remote now there are a lot of emerging Technologies it’s good to in fact one’s been around
For a while uh as a company that do remote monitoring of corrosion I think that’s really good depending on the size of the project if it can if you can sort of justify it I think that’d be a huge bonus for your client you say the building owner ultimately um but yeah
Keeping water quality um clean you know good water quality with the right level of uh controls and we’ve actually in fact took some old systems and we’ve managed to save uh save the client you know a significant amount of money on gas by using iot smart devices along with our water quality approach Um the other thing to consider is plant upgrades and integration unfortunately um some people have an expectation well I’ve just installed this new boiler and I’ve got all my heat pump I’ve got new equipment I’ve added it to the system and but I want a bizer standard I want a
Bizer standard for this old system and you know that is if I’m honest kind of pie in the sky because it’s one thing trying to hit a bizer standard for new systems but when you’ve got an old you know could be 50- year old system you
Might be connecting to on a you won’t achieve or you could do potentially but I’d say you know manage expectations trying to maintain water quality in that sort of system would be very very challenging so I think you have to to have a bit of pragmatism of how you
Approach the secondary side I mean one thing we promote typically is if you’ve got an old system go for a passive nonf flush cleanse of that system um so you know filtration with non- flush additives if you can do that sometimes old systems just inhibitor it’s not
Ideal but it’s again you we don’t want to sprinkler a system on that secondary side and this gives you an idea of what we’ve manage to pull out um of systems this is with our xot and um just inhibitor so one hour this was my this
Was some years ago now in fact that’s me modeling my hand with a magnet grate there but that was what we pulled out after 1 hour and then um 12 days later you can see in the middle just how much had come out of this 50 year old it
About 50 year old system um and I actually remember anecdotally there was um the people that work in the store it used to be a cinema then then it was a boots um and uh yeah they they always had trouble in a hard winter getting the
You know the place up to temperature um it later trans trans insired actually the boilers were undersized as well but um by cleaning up that system we got the air handling coils the onoff air temperatures were were much better um and the staff said it was the first time
You know it hadn’t been cold in the winter so again the impact overall on the efficiency of the system it could be huge um older systems again coming to that passive long-term clean is more effective for age systems before you upgrade and when I say that what I mean
Is is if you know that you know your client wants you to to I know do a plant room refurbishment and you’ve got to connect to an existing circuit the best time to make a difference for that customer is actually going to be you know three six months
Beforehand I mean I’ve seen systems take a year to get clean when we do a a passive non you know non-invasive approach which is basically using additives to gently remove uh deposits you can see the top left picture there that was that was um coming out of a 25y
Old plus system at a university and that’s magneti and biofilm you can see on there um somebody’s holding a magnet grate and the picture to the right was the main primary header in an old school so um you can imagine you know doing a quick flush a week in a week you know
Even over the course of a week before you connect your new equipment even if you’re going to put a plate heat exchanger on there to protect that new equipment what’s coming down the line into that nice new plate heat exchange it’s just something to consider so i’ well we would certainly recommend um
Getting in there early as soon as you can because at least when the contractor isolates and does uh the plant room drain down you’ve already tackled the existing secondary um just some examples there of what we can pull out of uh the system but also how quickly then you can clean
Clean your magnet great and get your water quality I mean you can see there how clear that is so xot um again uh as well as other filters again I can’t just promote our product any filtration ultimately is going to be a benefit to systems um that you have so if you’ve
Got all dosing Parts recommend you do retrofit them with some form of a filter otherwise all you’ve got is an empty vessel so if you can retrofit that for something that’s going to start pulling out these solids can make a huge significance to uh to your system to the
Efficiency and we sort of just getting through module 3 now uh coming to a close uh before Q&A so obviously there’s a lot of information to take in there but ultimately as Engineers as somebody designing a system you know what should you be telling your customers or how you
Safeguard your customers to ensure your project is delivered on time at the right level as well of quality uh and knowing that you’re going to be able to give the building owner the model that you designed from Cradle to grave so water quality is key I hope I’ve sort of
Made that clear really through the the slides I’ve showed you but today but um what I would say is that you know rely on the Professionals in the field um different levels of Professionals in the field I would say but um the um there
Are places you can go to so one of the things I’d recommend is that within the specification any water quality company sorry any water treatment company that would come into your premises or come into the site to do any water quality um just specify they should be a member of
The csca um this the close system Control Association this organization basically audits rather like Legionella professionals you know uh the practice Legionella mitigation um have typically doesn’t have to but typically are members and highly specified if if anyone wants to look after a hospital for example chances are a water
Treatment company are not going to be able to take on any contracts without being a member of the Legionella Control Association not many people really know about the csca but I would advise take a look at them have a look at the website they vet uh the Water treatment
Companies so if you’ve got three prices coming in you want apples for apples not just oh this one’s coming much less uh the contract will naturally are we’ll go for that um I don’t know if it’s still the same same but many years ago um I
Found it was very much packaged up with the m& contractor um when it came to the water quality but at least with a csca you know you’re going to be getting apples for apples um metaphorically speaking when it comes to quotations um other things I put in there you know specify lead technicians
At least have a minimum of three years experience and appropriate evidence of training and a cscs supervisor card you want to make sure you’re getting banged for your buck as it were somebody coming on site it’s an important very important job um that needs to be conducted it’s
Got to be done right at the front end other other areas we’ve been working with luur University um supporting a PhD and we’ve seen significant savings um by uh cleaning up existing systems um when you consider the amount of energy in a commercial building that’s
Been used um and this is actually I need to update this I do apologize because now there is a sibsy guide M that’s come out this year um there’s been an update to it but essentially we using a huge amount of energy in a commercial building associated with heating and hot
Water and so unless you’ve got direct fire cylinders uh even the hot water is coming off your your core heating system so actually if that water quality is not right you can be significantly impacted in that efficiency of that system you know anywhere from you know up to I
Would say potentially 20% you know you could be losing efficiency because your pumps are working harder your strainers are getting blocked so your pumps are ramping up um you know your heat exchangers your boilers are struggling so people generally I’ve seen over the years turn up the the thermostat on the
Boiler the temperature stat on the boiler and some on to try and push heat around so there’s a huge amount of savings as well that can be done with energy um just by having clean systems but getting back to biofilm so scale is a as a therm insulator we we get scale
On our boiler it’s going to be putting more gas in or more energy in to to meet the same level of demand to put the of energy going out and actually biofilm is is is a greater Thal insulator so having biofilm on our evaporator coils in a
Chilled in a chiller or even the condenser or um or even in our you know even in a boiler and in our radiators you know um bacteria is is can bofilm can can create significant loss of energy um particularly where we have um a lot of hius uh heat interface units
That being stalled um there was a a big surge wasn’t there on the renewable heat incentives and you know biomass for example uh things like that you know there’s a huge amount of um incentives so a lot of these systems installed but certainly a lot of District heating schemes that are being
Installed now feeding up to hiu units um you will have errors on the heat meters so the Esco whoever’s providing the energy um essentially will be losing money potentially I mean we certainly have um some thermal losses anyway that is calculated into like a hold a standing charge but certainly at the
Meter itself if you have if you have turbid water it will throw out the uh the requirement sorry the the accuracy um so if you are looking to select uh any kind of equipment but let’s say focus on on filtration it’s really important to work with the um and assume
Not assume sorry I take that back work with the the OEM or the manufacturer of the equipment you’re looking to install uh but also just make sure you double check do your own homework that you you you know you’re selecting the right equipment and I don’t mean that you know
I don’t mean that in any sort of demeaning way um but yeah selecting the right equipment at the right size the right operating temperatures to meet the demands of that system I’ve come across problematic jobs where again pressure vessels weren’t sized correctly uh there’s been pressure step to gasing on
Heating and the temperature of the system is way hotter than the manufacturer recommends for their equipment so you start having all these issues and and it can take months before you get to the root cause U Biz do recommend um if you are using any kind of filtration for a
System you have some form of an alarm system to ensure that you uh you can change that filter you know when that filter needs to be changed um you know and if something’s difficult to maintain it probably won’t get maintained or if it’s out of sight it’s out of mind so uh
Really really key that understanding any equipment you install for any application really if if there is a servicing requirement um you really make it you know foolproof that somebody knows it needs to they need to come and change so cradle grave sampling um bsria States the frequency um but I do
Recommend the British standard um really do support um where you should sample from they also support the frequency and Biz help you to interpret what those samples look like so again um I guess these slides will be available in any case so when you look at the resourcing
Or module 3 uh these are these are great um places that you can go for information that’s just a bit of a pitch on uh some work we’ve done in the past where we’ve seen energy savings within a week 3 and a half% on one particular building and unfortunately the filter
Blocked um and then covid happened so um that whole that whole trial has been running running again actually so we’re waiting for the outcome um and on the right we actually working with Dr Raina mayor many years ago about 10 years ago he by adding inhibitor in his system um
It took three years he kept dosing every year and after the third year um he’s no longer had any kind of gasing didn’t have to drain the radiators and he you know he felt the difference on the radiators in terms of heat output so you know water treatment is not it’s not
Snake oil it’s not you know black magic it is literally it’s all about chemically managing your system um there’s just some slides here I’m going to have to just mind for the time but um there’s some slides here some work we’ve done with L University various uh analysis were carried out I
Mean the we even saw you know saving or restoring up to 83.5% of the energy use going into a pump and I have to say I mean that bear in mind that is is in a lab condition so it’s you know it’s under a very much kind of magnified condition but I think
You know the arbitrary sort of uh number I would say is you know you could be losing you know 19 20% on energy if you’ve got you know fouled strainers poor water quality in your system so it’s always been a difficult one oh you know how much is this going to save me
Like all all questions come ultimately what’s the return of investment but what’s the return of investment you need to ask yourself if the water quality in that system you know is so poor um that the pumps are working harder and you are having failures and and pipe work is
Leaking and you know I think we can all associate that if we’ve got poor water quality we’re going to be heading in that direction so that does have an impact on on the uh in terms of the the efficiency of the system um what we also found as well is
Is the relevance of of pressure and uh the amount of sediment that was added to the system as well so the higher the pressure what we actually found was we we were actually pulling more out of the um out of the unit but it was blocking much quicker which one would expect but
Because in this case we were using the system pump and we only had the one pump then that’s hence the correlation but um typically most systems are operating over a bar in a commercial system so again resources Biza uh if you looking for the chemical SL filtration I
Think you should always have filtration regardless but um certainly if you’re looking for a chemical approach uh which is generally the most common approach in the UK um bizri are you know it’s not a standard in the sense of it’s a guide unfortunately and even in the latest
Publication they try to make the point that you do not need to uh or you shouldn’t be using it contractually um you know as a standard it is a guide and each each system and each site can differ but they unfortunately is still very much people
Are held to that number you know that’s what it says in the bizer guide you need to hit you know this level of iron needs to be below this much therefore you got to flush the whole system again and it’s just it’s just not necessary really I
Think um providing that you can prove you know you don’t want something too far off the bizer guys but providing you can prove that you know in terms of scientific Trends the corrosion is under control you know microbes are under control um you know you’re winning essentially but um a great great place
To go closed system Control Association as I say they they pretty much if if you recognize that them and you put them in to say you know in a spec uh we want water treatment company specialist must be a member of CSA kind of takes away the whole Biz stuff because that’s what
They should be doing um and then really good guide here it’s not a huge book to get through um but the yeah BS 8552 2012 uh Cradle to grave uh in terms of sampling where you should sample So based on system volume how many samples
Do we need to take I said I would touch on the German vdi um so it works if it’s professionally planned uh and constructed system so going back to what I was saying is if you you’re looking to deploy the vdi standard and avoid use of
Chemicals which I think is a great idea if we can do that um then yeah uh we we should certainly do that but you you need to make sure that right at the very front end um you know you are you you are designing that system appropriately
Because it relies on um you know you don’t have any Ingress of oxygen at all um I mean it can handle it but it’ll impact the equipment ultimately if you have too much of a water loss but the German video because it doesn’t rely on chemistry sorry adding chemicals it
Relies on uh essentially removing oxygen from the water if you remove the oxygen you don’t have corrosion and what makes water more corrosive well obviously oxygen does but also something actually the conductivity of the water can make water more corrosive so naturally if we had imagine you know demineralized water
Very low conductivity we start adding our chemicals we’ll see the the conductivity start to increase however we’ve got Inhibitors in there that mitigate any kind of risk of corrosion because of the conductivity um but with the vidi standard they take the oxygen out um you remove the mineral content not all of it
We don’t want completely totally removed because otherwise we’ll end up with leeching of like brass fittings Etc so it’s normally about 100 or less 50 to 100 micro semans um I recall when it’s the vidi standard uh and they use a sacrificial ano so it has a magnesium
Sacrificial anoe that’s used within this cylinder um that will sort if you like take the hit rather than the pipe work you know it’s a bit like they do on ships um it’s quite I say new I think it’s been in the been here probably five
Six years we’re starting to see more it started we’ve seen it come across it’s starting to prove more popular vexo are actually uh investigating with a a manufacturer something uh working on something for us as well because we don’t want to say no to customers we
Don’t want to say no we can’t offer you an alternative and Vex we’re a green company um you know we pride ourselves in being green so if there is something that we feel comfortable with um and we’ve done our field test as well um then absolutely we’ll join join in and
Offer our clients that depending on their application and what they what they need but um that is the non-chemical treatment approach the only danger not danger the only downside to that you have to consider is the ongoing so you don’t want a dosing pot for example really if you can have a vdi
Standard approach because the minute you add chemicals into a system that is using the vdi it it throws the whole thing out you know it’s it’s um going to cause issues um oh no last slide so um yeah that’s me so I’m happy to um to take any
Questions you may have thank you thank you Darren that was uh excellent and really informative thanks very much and and in fact I think you’ve um answered a first of a couple of questions one was um from Terry vdi 2035 and bg50 should they be treated as a comparable document
And then I’ve got a comment from Ben who kind of answers that by saying I think bg50 is based around chemical dosing and filtration while vdi 2035 is based around chemical free treatment yeah absolutely so they’re totally two different approaches and I think that’s the educational piece
Whichever system you go with um you you need to be sure that you don’t add chemicals in a system that’s chemical free because it has an impact yeah and and Ben then adds to that comment I think export is fantastic but doesn’t create the water quality specified in
Vdi 2035 which I think is increasingly being viewed as the preferred water quality standard although maybe not fully recognized in the UK yet absolutely so um I think you know filtration on its own whether it’s it will Aid whether it’s vdi or whether it’s uh chemical treatment so going back
To existing systems the minut if you’ve had a you know have a 50y old system that’s got no treatment in there at all but the water quality is clear to look at it’s probably because obviously all that oxygen was used up in the process of corrosion and it settled out um and
Certainly if you’ve not had too many leaks thereafter the minute you add some form of an inhibitor you’re going to start to lift that and you’re going to grab it you’ll get uh increased efficiency and performance but uh you know same with the vdi if you’re looking
To approach the vdi on an older system or even on a newer system vdi might give might it may control the corrosion that’s what it’s doing it’s controlling corrosion but if you you know nothing’s ever perfect if you have any kind of deposit in that water that that acrs or
Is developed anywhere in the system whether it be a dead leg what’s going to happen it’s going to circulate around that system so that won’t control um erosion corrosion for example through those particles so a good form of filtration on any system is is certainly recommended but you want to avoid um
Encouraging people that you know let’s say you put an xot in a vdi system my advice would be take off the funnel cap it and make sure there’s plenty of signage around that plant room area that any water treatment company that because they’ve always done it this way it’s
Quite clear do not be chemicals in our system you will be liable exactly um question from Douglas in what form does the automatic monitoring system you mentioned take okay um so typically it’s made up of various sensors um dissolved oxygen pH pressure uh sometimes flow rate but certainly
Conductivity uh and then a galvanic corrosion sensor so you’ll have these various sort of sensors and you can get a tability test sensor as well which is suspended solids essentially um and you can they can be connected remotely and accessed on a cloud platform so there’s
A company called heaw they have um they have some products available they I think they’re the first really to bring it to Market I think there was another one I’ve seen recently which is a company working with one of the vdi manufacturers so again great idea if
Oems are coming together um I think it’s a great idea um so yeah there are products available obviously come they do come at a cost but it depends on the equipment if it’s a small little heating system uh versus a district heating system I think a district he heating
System or much larger assets would would make sense to have that it’s early War early warning indicator question from Richard hi Darren thank you for a very interesting presentation what method of sterilization do you prefer for system makeup water I pressurization unit feed water um so some some manufacturers will
Add biocides each time it something it makes up um UV filtration can be a form of sterilization as well um or potentially you know sort of I’m guessing the Americans would say spitballing here but you could even have a holding tank um that you pasteurize you know every so often and then it
Pulls from there there’s you think of different ways of where you could kill or mitigate the bacteria that would be coming in thank you uh question from Tom what are the differences advantages and disadvantages of systems like the xot and a sid stream filtration unit um I guess the export and S infiltration
Essentially one of the same so both are installed in side stream or you know they can be operated on without shutting the system down um I guess pros and cons versus say just so understand the question correctly because they’re essentially the same they’re more or less the same I
Guess the pros are you’re going to capture much finer particles um you know that that would normally be liberated around the system the cons really come from um more over if it’s not maintained so it’s really important again that you have some sort of alarm system that you know so that
Would be the cons because that could then start causing you an issue adding to your problems potentially as well or people think I’ve got a side stream filter and they walk through the plant room and they don’t do anything about it they they just know it’s there no one’s
Checking the water quality so it’s it’s You’ got to be holistic in in in the approach in any any system well I think that’s it uh in terms of questions Darren um and again um like to thank you for a very informative excellent presentation uh uh very much appreciated
By those who attended just to let everyone know that this recording is available on the siy website Darren is going to send me a copy of his presentation which again we’ll put on the on the siy home county Southeast page where you can all download so it uh
Yeah just leaves me to say thank you for everyone who attended tonight and again thanks Darren excellent presentation thank you enjoy your evening everybody you enjoy yous thanks again bye bye cheers bye bye