Ferroli F24 Bioler

[Jacko439]

Had a call from my daughter this morning to tell me that the water pressure was reading below 1 bar when I got there it was turned off and cold reading 1/2 bar. I pressurised it to 1.1/2 bar from cold and fired the boiler up in a short while the radiators were hot but I noticed the pressure had risen to 3,1/2 bar when the top pressure on the clock only reads 4 Bar.
Is this normal and I saw from the instructions that to lower the pressure below 2 bar shut boiler down for 20 minutes and run hot tap for five minutes. Should I have carried this lessoning of pressure out?

Answers to my problem would be warmly welcomed.

[The Builder]

It's quite normal for pressure to rise to around 3 bar or more when in use, Jacko. Water expands when hot. There is a pressure relief valve so that any excess pressure (anything up to 4 bar) will simply be relieved by a pipe leading to outside the house.

3.5 is high though. Perhaps the relief valve is not operating as soon as it should. Stick a milk bottole or jam jar over the external pipe and see if it fills.

Running a hot tap will have no effect. Hot water is mains fed. It has no connection to the radiator (system) circuit.

[Jacko439]

I should also perhaps have said that it was just slightly above 3.1/2 and still rising I got worried and turned the boiler off at this point and it soon started to lower the pressure.

[Baldric]

If ever I've needed to lower pressure quickly I've opened a radiator bleed valve.

[The Builder]

I think I would have the pressure relief valve checked, Jacko.

[BRIGHT SPARK]

A healthy system should not rise 2 bar during use.Does it rise on standby?

[Jacko439]

The daughter has rung to say that she has shut down the system and is in the process of bleeding some water out of the system this seems as though it has add the
desired effect as the pressure now reads 2.25 Bar. Will keep you all informed when I myself know more but in any case thank you all for your help.
Jacko439 ex RAF.

[Jacko439]

Thank you all for your help in this matter the daughter tells me that she released some water pressure by means of the Bleed valve and since doing so the pressure has remained the same. To answer the question posed by Bright Spark the pressure remains constant when in standby mode. Based on this I think the problem is now solved I am however unable to pick a best answer as I consider all equal. Once again thank you all for your help.