Appliance Repair Questions? Ask a Technician for Answers ASAP
Good morning, welcome to the Technical section in JustAnswer; my name is ***** ***** I will help you today.We need to work through this systematically, so there will be some tests I ask you to do, and monitoring over a period of hours, so please don't expect an instant answer. I'll come back to your specific questions shortly, but first please secure a polythene bag ( with no holes in ) under the end of the copper discharge pipe on the outside wall where the boiler is mounted. Top up the pressure, preferably when the boiler is cold, and then wait for the pressure to fall. Then let me know if there is any water in the bag.To be objective about this, please tell me the following pressure readings:1. Before you top up;2. After you top up;3. After it has dropped again.Also, please provide the make and complete model number of the boiler._____If you receive a phone call offer, please ignore it - these are system generated and outside my control. My understanding is that you won't be charged if there's no phone call.
Impeccably clear and accurate answers - thank you!The amount of water that you're adding is going somewhere, and unless it's being sprayed into the combustion chamber through a hole in the heat exchanger and disappearing out of the flue, then it must be leaking from the primary pipework somewhere. If it were leaking from anywhere on the 1st floor I would expect you to have seen water on the ground floor. If it's leaking from pipework under, or embedded in, the floor, then of course it could be disappearing.You mentioned closing the isolating valves on the UFH installation. You can't assume that the valves are working, so do you have a pressure gauge on the UFH manifold in evidence that no water was being lost there? If not, then install one pronto!(BTW, on a pedantic point, as a contractor I would never report that "there is no problem" when looking for a leak and inspecting something. All that anyone can saw is that the fault hasn't been found yet, and until you know where it is, nobody can say where it isn't. This is more than just an existential conundrum - it's important to stay open-minded in a hunt for a leak, and mentally closing off possibilities is conducive to making mistakes.)
Apologies for the delay - I was out for a while. I will digest your post now and reply ASAP...
Leaks in UFH systems to happen, but lets stay positive. Even if you have one, you don't necessarily need the entire installation to be dug up - there are specialist ways of detecting the location of the leak and then a localised repair can be done._____There is an easy test for you to do without having to pay your engineer to do any work. All it needs is for you to identify and operate the two isolating valves for the UFH. If you don't know where they are, please take a photo of the UFH manifold and the area around it, and I'll tell you where the valves are. The photo doesn't need to be a close up, just in focus and well-lit. After that I can tell you the steps for the easy test.
Good work. Yes I can see it. Bear with me...
Sorry for the delay - I was on a phone call. Please could you take a much wider angle shot of the manifold and surrounding pipework?
Excellent! Now, do you have a radiator vent key? Something like this one?
OK. On the upper right of the manifold there is a vent. Your key should fit that. Get an old towel ready.
1. Assuming that both red and both blue valve handles are still in the closed position as shown in your photo, go ahead and open that vent. You should little or no water emerging. If you do, it should peter out very quickly.2. If the water doesn't stop pretty quickly, that suggests that at least two of the valves don't work and you can't continue. Let me know if that's the case.3. If the water stops, then check the system pressure and top it up if needed. When the pressure is up to 1.0 bar, if water is still not coming out of the vent, then the valves are working, so close the vent, and open both of the blue valves, then close them again.4. Wait 24 hours.5. Repeat step 1. This time you should get a stronger jet of water that might last longer before it peters out.Let me know how all of that goes.
1. You don't need to open the other vent. It would do no harm to open it, but then you have two vents to close, and if you want to do so in a hurry then that can be inconvenient.2. Yes. My step 2 should have said "Close the vent and let me know..." Apologies. Well spotted.
Hi PaulOK. Give me a moment to refresh my memory of the steps - 24 hours is a long time in the heating industry ;-)
Right. That is a strong confirmation that the leak is not in the underfloor loop. That's probably good news for you.However, it doesn't solve the mystery because you still have a leak somewhere. I'm excluding a heat exchanger leak because you lose pressure when the boiler isn't burning. As I said at the outset I doubt that it could be from the first floor, so the focus now should be on the ground floor.Do you have concrete floors throughout, or some suspended floors?
Hi Paul"screed throughout" is the answer to my question, so that's fine.If you're absolutely 100% certain that nothing is coming out of the PRV discharge pipe, then I think your next step is audio and heat tracing. With sensitive leak detection equipment, accurate tracing can be achieved of water 'squirting' out of a leak in concrete. I don't have that equipment but specialist leak-tracing contractors do, so that's the direction I would be going now that the obvious suspects have been all but eliminated.
Hi PaulThat sounds like the service you need. I'll just have a quick look at their web site...
Yes that sounds professional. I can't see any spelling mistakes on the web site, which bodes well. And I like this:"On completion of our Leak Detection Survey we provide a fully comprehensive leak detection report including colour photographs and recommendations. You will then be able to make arrangements with your local plumber to fix the leak."...so they aren't trying to tie you in to using them for the fix.
You're welcome, Paul :-)This is an opportune moment to ask you to rate my assistance, using the 5 stars at the top of the page. The customer's rating is what enables an expert to be paid for their time, so I'm glad to hear that I was helpful to you :-)
Thank you for your rating, Paul, and your very kind bonus :-)
By the way I will be interested to hear the outcome!
You can always email me at :***@******.***