Pressure Testing Your Underfloor Heating System

[@chiragg5739]

This is an excellent video and capture all aspects. Will surely help me pressure test my system now. The supplier only gives instructions on paper but your video is spot on. Thank you.

[@MultipipeLtd]

Glad it was helpful!

[@brianruane8505]

Its a very good, clear explanation - and he mentioned the correct pressures too....TOP MAN!!

[@CarlosMendez-hs8yi]

Great vid mate very understanding will be fitting underfloor heating at my house thanks

[@MultipipeLtd]

Glad it helped

[@adaesco]

Would you close off your auto air vent on the manifold if it had one fitted? Just thinking if it vents air your pressure would drop whilst leaving on pressure test

[@MultipipeLtd]

Not if you are wet pressure testing. Venting the air first is vital as compression of air in the system can give false readings. If, however you are air testing then yes ensure it is shut.

[@aleksandarstojanovski1005]

Great educational video, thanks a lot. I'm having a question regards this. I'm having 130 m^2 floor, and I'm planning to cover it with 13 circuirts, open loops system without actuators and buffer tanks. How can I be sure that my pump can drive all od the circuits well. My pump can maintain flow 25,8 L/min for delta 5 at 35 degrees celsius and it is variable speed pump with 32/102 input / output watts. Can I go with a single manifold or I need to split the instalation on multiple manifolds?

[@MultipipeLtd]

if you send your project to us we can check the duty and ensure the bar on our manifold is good enough for the pump send to [e-mail]

[@BigGoldenApple]

I had my UFH commissioned today however the Gas Safe engineer haven’t pressure tested and have asked me to leave the UHF running for few hours and switch it off to cool before screed. So is a pressure test a must? Is pressure test only to test for leaks? If there are no leaks under a working pressure than can you still proceed with Screeding? Please advise. Thanks

[@MultipipeLtd]

It is highly recommended to pressure test past what the system will run at. This ensures the chance of failure before you permanently screed in the pipe is minimised. Remember, that pipe is going to be embedded for the next 50 years +. At the very least when screeding the UFH system should be pressurised.

[@BigGoldenApple]

@@MultipipeLtd Am I correct in thinking that the pressure test is only performed to check for leaks under high pressure? Or is it also done for the maximum pipe expansion before the screed? Many thanks.

[@MultipipeLtd]

@@BigGoldenAppleThe first part of the test is to check for leaks (normally around 4-6Bar). In the second part, you reduce it to system pressure (around 1-1.5Bar) then screed with this. It is to ensure you do not crack the screed or squeeze the pipe.

[@garydawson9251]

are you saying to screed with it at working pressure or the higher testing pressure?

[@MultipipeLtd]

Screed at normal operating pressure, as when the screed is curing, you do get changes in pressure, so a lower pressure ensures you don't run into any issues.

[@garydawson9251]

Much appreciated.

[@zaksystems]

Can you do one on single zone UFH. Can a zone pressure be seen from the boiler? Can more pressure be added by the boiler?

[@MultipipeLtd]

Many thanks for your message, We will put down to do a video on the single zone pump unit. Thanks for the suggestion. Unless you have hydronic separation, the system pressure is generally around the same no matter where you are in the system. This is only to provide a positive pressure in the system for pumps etc., to work. This video is aimed more at testing the system for leaks. As per our earlier video on filling your system, you should fill the system and then "top-up" the pressure using the boiler fill loop when required.

[@raybahadur6555]

Your video is great help first time installing tomorrow 🤣 just wanted too ask you use the red pressure tester and I haven't got that, can I just carry on filling up from cold tap using a pressure gauge

[@MultipipeLtd]

I am glad they helped. The issue is the cold water pressure in the UK is around 1-2 bar, whereas you need to test higher than this a minimum of 4 bar. However, you can pick up a pressure tester for not very much. Being as you plan to bury the pipe for the foreseeable future, it is worth the investment.

[@raybahadur6555]

@@MultipipeLtd thank you so much for replying back too me as I will be doing this job in the next few days, I will buy a pressure gauge not a problem I was asking if I leave the gauge attached and keep filling from my mains cold rather than the red pressure tester you have. I am sure if I keep the cold water attached and the pressure gauge it will get too 6 bar.

[@raybahadur6555]

@@MultipipeLtd can I achieve 6 bar pressure just using the mains cold water as I dont have a pressure test pump

[@MultipipeLtd]

@@raybahadur6555 ok, so in terms of filling the system, you need to watch our other video as you need to push the warted through the manifold (filling from a cold water loop would take an age). see: kzbin.info/www/bejne/aX7Vo4Odgbenq68 . if you can get 6 Bar on the main, that's some pressure. But you are correct, then you would not need to pressurise more. Just keep the little gauge attached for 1 hour and look for no substantial drops. then drop to working pressure before screening. I hope that helps :)

[@Stile30]

Is it possible to close all UFH circuits except one and then to measure pressure on only one circuit and not on all manifold installation? I want to pinpoint if one exact UHF circuit is leaking. I am not sure if 5 bars will be to high if valves for other circuits are closed as well as flow meters?

[@MultipipeLtd]

Apologies for the delay in coming back, providing the seals are good on both the flow meter and the actuator pin there is no reason you cannot lock down and pressure test each loop. As you don't know the state of the seals it best to lock down the entire manifold (all flowmeters/actuator pin and primary ball valves) then release pressure on the bottom bar (open the drain) and pressurise the top in theory no water should come out the bottom then open the flowmeter only one by one until you start seeing a drop.

[@Stile30]

@@MultipipeLtd thanks for your feedback. Greatly appreciated!

[@SimonSideburns]

I've been watching your videos and they are very thorough. I've been installing my own ufh system and I'm really enjoying integrating it into our existing boiler and radiator circuit. After watching your filling video I have put mains pressure into the system, and I was surprised my gauge was at 4.5 bar once I closed the valves and disconnected the pipe. Within an hour or so the pressure has gone up to 7 bar without me putting any additional water into the system. Great news is that there are no leaks so far, so do I need to use one of those hydraulic testers?

[@MultipipeLtd]

Thanks for watching! all a pressure tester is for is raising pressure in the system to a level required to test for leaks in UFH that is 4-6 bar. so you are good to go. However, I would question the accuracy of the gauge as mains domestic pressure is normally 1-2 bar only. also, pressure in a sealed system can only go down not up.

[@SimonSideburns]

@@MultipipeLtd Would sunlight heating the pipework cause it to warm up and increase the pressure? The room we have laid the pipe in gets the sun from around midday to sundown, and the foil-covered insulation does get warm with the sun on it.

[@MultipipeLtd]

If you have additional questions, feel free to leave them for us in the comments below. Thanks!

[@MitchellHBK100]

Hey guys, I watched the video where you are filling and opening the flow meters one at a time and then closing them one after each other, however the actuators you don’t seem to close them? When you’re filling won’t it go down into the next loop? I would have thought you open one flow meter and one actuator port and flush water through and then close both them and move onto the next?

[@MultipipeLtd]

providing all the flow meters are shut and you only open one at a time then it cannot flow back as the water will be flowing over the flowmeters, you are only shutting them to provide more resistance than the loop you are filling as water will take the easiest route and flow out of the drain rather than backflow and push the flowmeter up.

[@MitchellHBK100]

@@MultipipeLtd so open one flow meter and open all actuator heads/returns. Then fill and close flow meter and then move onto the next flow meter and once all filled open all flow meters. Brilliant thanks guys

[@Bud-vd2xd]

Hi Martin, you have helped on my recent installation with your great videos. On the pressure tester I have a 15mm female connection, what do you use to apart it’s to fit the 3/4 tap connector on the manifold?

[@MultipipeLtd]

Hi! glad you like the videos, most pressure testers have a 1/2" connection they are slightly different but for this one i just used a 1/2" Male Iron into the tester (with thread tape) bit of pipe then a 3/4" Union connector so it gives you a nice easy way to breakout after you finish (just remember the flat face needs a washer.

[@GamerLife2940_]

Before screed goes down what pressure should it be please? I think mine is around 5 bar

[@MultipipeLtd]

apologies for our late reply, the pressure when laying should be dropped to around 1-1.5 Bar. This is enough to allow the showing of leaks (the pressure drops to zero) but not enough to cause damage. As the pressure will vary a lot during the screed curing.

[@terryupton7623]

I have a situation where the UFH system has been installed for just over 5 years and this winter it struggles to heat the room (air) and never manages to reached the desired temperature (20°C). The floor ins't cold but is barely warm even after running it for many hours. Everything looks ok and is running in the manifold and the pipe coming from the boiler is scorching hot. But the loop pipes leaving the manifold and all thr pipework in the manifold itself don't feel very warm. Could you make any suggestions as to what might cause this situation or what I should look for or can try myself, before I get a heating engineer out. Thanks.

[@MultipipeLtd]

A good UFH system should never really be warm under foot (if it is then it probably overheated). but firstly get yourself a cheap spot temperature thermometer and check the floor surface temperature this should be no more than 29°C. If that is the case than the UFH is fine but its more your building is loosing more heat than the UFH can produce. There is other things we can try just call us on 01245850799 to discuss further.

[@captainzeppos]

Why can't I have such a fantastic technician close to where I live? It's just unfair. The local plumbers are cavemen compared to this guy.

[@mrduncansmith]

Great vid, my installer has 'air' tested my installation as the house is still at first fix stage and unheated through the winter. Pressurised with compressor to 2 bar but drops to 1.5 after a week and then gradually drops further from there, anyone any idea if this is expected behaviour using air over that period?

[@MultipipeLtd]

Air testing is fine and you would expect a drop on initial pressurising and it could be as much as half a bar (known as settling) . However, what you don’t want is for it to keep dropping as this usually indicates a leak. Check to make sure all the valves are shut to the system and that any automatic air vents are completely shut. Unfortunately, with air it is hard to find a leak if you have one. I would get the installer back to check the joints as well.

[@darranbarker7]

hi there, i noticed you dropped the pressure to 2 bar prior to screeding, i have fast set screeding being laid and there will be a certain amount of heat during the 48 hour curing time, will this heat build up pressure in my system more than it can handle? or would i be wise to drop the pressure maybe down to 1 bar?

[@MultipipeLtd]

The pipework we sell as part of our system is designed to run at 10 Bar @ 80°C, so to have a system pressure that high would normally not happen (as your safety valve on the system is normally set lower than this). Of course, other manufacturers might have different pressures, but this should not be an issue.

[@hennx55]

Your video was very helpful and easy to follow, unlike the countless others that I've consumed. I might have a new revenue stream for your business, I would actually like to pay you to do a Zoom call with me to walk me through purging my system. The system is about 2 years old and it seems as though it is air-locked, since the floors aren't as warm as they used to be. If that is something that interests you please let me know. I'm sure you can get a ton of people much like myself to consult with you for help with simple jobs such as this.

[@MultipipeLtd]

@hennx55 many thanks for your message this is something we have not considered for our business as we mainly did these video for installers of our own systems. However, I will discuss this with our management about the potential of offering this service. please message me at [e-mail] your issue you are having.

[@ابونرجسللتاسيساتالصحية]

Good test

[@MultipipeLtd]

Glad you liked it

[@DanicaCourtois-m5j]

Dach Roads

[@AmaliaSchavone-t7b]

Harris Knoll