Pressure dropping on ravenheat codensing boiler

[revolver]

We had a ravenheat condensing boiler fitted a couple of months ago and it has consistently lost pressure over time. Whenever it drops below 1 bar I repressurise it from the refill line but the pressure drop continues. I have had the fitter out and he couldnt find any leaks, but something is obviously wrong. One thing - even with the pressure on the gauge below 1 bar it never cuts out. Is this related to the fault? I am worried about introducing fresh water into the system regularly.

 

[JohnD]

maybe he can't find the leak, but there is one.

Is water dripping from the pipe that sticks through the wall?

Have you got any pipes running under the ground floor or in concrete, where you can't see them leaking?

Any rusty or dirty marks on radiators or valves?

What does the pressure gauge read when hot and when cold?

 

[revolver]

there is a little water from the pipe thru the wall, but not as much as i seem to be putting in...........

pressure cold is say 1.2 bar (although obv. this varies over time...), will rise to approx 1.5 on heating.

 

[JohnD]

there is a little water from the pipe thru the wall

This is probably a relief valve in case of overpressure. Once disturbed they tend to drip. You may need to have a new one fitted.

If your previous engineer did not notice this, you may like to ask around friends and neighbours for a more recommended one. Tell him about the drip and the pressure loss. But look for any other signs of leaks too.

Did you have the old system powerflushed when the new boiler was fitted? If not, old sediment will tend to lodge in places, including under the relief valve, and stop it closing properly.

 

[revolver]

thanks for your help. I'll get him out again, at least I have something I can check now...