Isolating Boiler Question

[wisiu]

Hello


I have a leak somewhere on my heating system as I am loosing pressure, before I will start to rip off my laminate flooring I want to isolate the boiler from the system by closing the valves on the heating pipes. Do I need to switch off the boiler from mains before I close the valves ? If not then can I use hot water ?

 

[Agile]

You really do need to tell us which model of Vokera (?) boiler you have.

If you do it correctly you may well be able to continue to use hot water.

Posting a photo of the pipework under the boiler might enable us to give you better advice.

I would also suggest you get our advice FIRST before you take up any laminate floors!

Also describe EXACTLY what the property consists of and what is under the floors!

Tony Glazier

 

[wisiu]

Thank you Tony, the boiler is Valliant EcoTec Plus 831, recently installed and the pressure drop from 1.6 to 1 bar within a day. There is no leaks on the radiators, no leaks on the valves, no watermarks on the cealing so the only option is a leak under ground floor. I have floating laminate and then timber suspended floor. There is a gap about 50 cm between the floor and the ground ( gravell?) and the pipes are there so I am planning to take off the laminate and check the pipes but I thought it would be worth to check the boiler before I do that. The company who installed the boiler sent the engineer last week to check exacly what I checked before so not much help from their side. They do not respond to my e-mails now so I am a bit left on my own with this issue.

 

[Agile]

I would guess that it was not a pressurised system before and that some joint was not very well made and has started leaking as a result of the increased pressure.

Presumably the 500 mm under the floor is from the floor boards so that there is only 400 mm from the underside of the joists?

I would crawl through a 500 mm gap but not 400 mm. In older times one would have used a small boy!

Pressurise your boiler to 1.6 bar cold and then close the two heating valves under the boiler. Don't mess up the valves trying to use a screwdriver. Instead use a "T" handle or long 4 mm allen key.

Then leave for at least 24 hours and see what you find.

Whilst the manufacturers and some engineers here will tell you not to, in my experience it does not cause any problems to continue to use hot water BUT if you choose to do that then do turn the water temperature down to below 40 C.

Tony

 

[wisiu]

Thanks again Tony, you are correct, the system was very old with open tank in the loft, it could even leak for years. I am not exactly sure how big is the gap but I can definitely crawl under the floor, the problem is that there are some construction walls under the middle of the living room so I will have to get access from few more points in my house. I have also rads in the conservatory but that was build not long ago and the pipes are plastic so I will check first the one in living and dining room. Another 2 rads are in the study room and downstairs toilet but from what I could see the plastic pipes are going from upstairs toilets down inside the plaster wall separating those 2 rooms so if there was a leak then it would come out somewhere, the floor is concrete so not possible to escape to the ground.


Thank you for the advice.

 

[Agile]

Usually its possible to make a small hole in the middle of a floor supporting wall to get through.

Most leaks seem to be close to rads and most often in the elbows underneath.

Sometimes its possible to look with one of the minute camera on the end of a cable.

Tony

 

[Agile]

But do check the boiler as I describe above before touching the floor!

Tony

 

[endecotp]

Have you checked whether any water has come out of the pressure relief valve?

I spent a long time looking under floors for a leak, only to eventually discover that the leak was from the primary heat exchanger inside the combustion chamber. I had checked for loss of pressure with the boiler isolated, but that didn't seem to work perhaps because the leak only happened when the boiler was hot.

 

[wisiu]

So I decided to start with living room, removed about 6 rows of laminate planks and cut off the hole in timber floor to get under. Managed to crawl without any issues, checked all the pipes and no leaks found. Next day I started with dining room, again detached some laminate planks and found that someone already cut off one piece of wooden plank before so it was easy to remove again. Straight after I found the leak!! There was a reduction from 22m to 15mm on the plastic pipe going to conservatory and it was leaking there, one drop per second, lots of water on the ground but it was escaping though the hole in the wall. The pipe was all rusted and covered with lime scale so it was leaking for long time, I couldn't even detach the pipe from one side on reduction connector so I had to cut off about 10cm , got all required bits from local shop and repaired myself withing half an hour. After filling the system back with the water the pressure is constant ( since 4 days) and no more leaks in this place.
I am glad I found it and it wasn't cooper pipe so easy to repair.
Thanks for help here on the forum.