Halstead Finest Gold - Loss of Pressure Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[LucyR]

The pressure on our boiler has to be topped up every time after the heating it turned off, as it drops down to '0' about an hour after use. (It only happens with the heating not the hot water)
The hot water and the actual heating works really well. Any advice would be very welcome!

[boilerbuddy]

If you have to re-pressurise your heating it means that you are losing water from somewhere.

Either you have a leak on your heating system, but from the amount of topping up you are doing, it is unlikely that you wouldn't have noticed it. I guess from the sound of it that the pressure relief valve in the boiler is letting by . Do you have water dripping from a pipe outside?

It is possible that the expansion vessel inside the boiler either needs re-pressurising with air, or that the pipework leading into it is blocked. You could see if this is the case by watching the pressure gauge when the boiler is running. If it rises inordinately, then there is a problem with the expansion vessel.

Whatever is the cause, if the PRV is letting by it will need to be changed.

Hope this helps