New combi boiler installed - loses 1.2 Bar pressure per day

[brompcarlisle]

Hi all,

I had a new combi boiler installed by a gas-safe registered engineer. We moved the position of the boiler so this required new pipes be laid - and so the floor was dug up, new pipes put in, and then everything was filled with concrete again. So a relatively major operation.

The problem is that the new boiler loses about 1.2 Bar of pressure every 24 hours. We have to fill it via the filling loop around every two days.

There are no obvious leaks above ground that I can find. I have got the engineer to look at it again, and he is talking about putting a blocking liquid in, but it seems the leak might be quite major so I don't know whether that will work. In people here's experience, how bad is 1.2 Bar per day and how likely is that the floor will have to be dug up so that the pipes can be re-examined?

Thanks,

 

[woodsy]

Far too much of a pressure loss which in the mid to long term will damage your system and boiler. A pressure loss of such an amount will / would not probably be sealed with the system sealer. It needs further investigation sooner rather than later.
A contractor with a thermal imaging device is probably required to locate the leak if it's buried which is likely to be expensive but will cause less damage.

 

[Killy Bing]

How big is the system as in how many stories is the house and how many rads + how big are they.

is there a red vessel next to the boiler?

did you previously have loft tanks which the installer removed?

leak sealer is unlikely to do any good in this situation.

the installer would have put a pipe outside the wall about a metre down from the flue, is water dripping from this?

 

[brompcarlisle]

How big is the system as in how many stories is the house and how many rads + how big are they.

is there a red vessel next to the boiler?

did you previously have loft tanks which the installer removed?

leak sealer is unlikely to do any good in this situation.

the installer would have put a pipe outside the wall about a metre down from the flue, is water dripping from this?

Thanks a lot for your reply (and the one above).

It's an Vaillant Ecotec pro 24 and it's a three-bedroom basement flat. There are six large/average size radiators. Previously we had an older boiler - it had a tank above it, on the roof of a small pantry bit sticking out the back of the block of flats. The old boiler and the tank were removed and a new combi installed in a different place in the kitchen.

In fact, the installer did not install a pressure relief valve that goes to an outside wall below the flue - at all! There is no pipe going out from the boiler where the valve should be, meaning you have to open up the front to release pressure.

There isn't a red vessel next to the boiler.

Hope this helps!

 

[Mike Jackson]

I would be looking at getting a second opinion. No PRV piped to the outside doesn't inspire confidence in the installation.

 

[village idiot]

If you are going to be concealing pipework, it is important to pressure test them. Seems your engineer did not do this. Expensive mistake. What happens if there is a leak (as you have now)? If pipes had been pressure tested, then pipework below floor could be discounted (well, likely). But my money is that floor has to be dug up again. BTW, how come a Combi has no PRV pipework? Except he has piped the RPV discharge via a tundish

 

[Ermintrude]

Cap off pipes at other end test for two days!

 

[Rickster123]

Lets see a pic of the install please.

 

[Reg Man]

It may not be a huge leak, but there is a leak all the same. Humidity testing on the floor/walls where the pipe runs are, and you may half a chance of finding the offending leak. As for the PRV discharge, concerns on the system design.

 

[WHPES]

Someone needs to cap of different sections to narrow it down.

There must be a pressure relief valve discharge somewhere. It may be internal within the house.

 

[shane]

For £20 try fernox leak sealer cheapest option first.

 

[Ermintrude]

£1400 to repair damage from using leak sealer over and over and over. 1.2 bar it's a bit of a drip.

 

[vern]

Leak sealer will sort around 0.5 - 1.0 bar over a week after that, start looking!
Just done one at a bar per day, after 8 visits from BG. I found 2 x speedfit ISO valves underfloor! Max rating of these is 65degs max! Glands had gone after a few years

 

[IDCHAPPY]

Leak sealer will never stop a 1 bar + a day leak.
your systems sure wont like taking in all that fresh water each day too... best find that leak ASAP