Ariston boiler pressure

[bobajob100]

What pressure should an ariston combi boiler run at when heating is on. When it is off it is between 1.2 and 1.5 but when the heating is on it goes up to 2.0. Is this ok

 

[Tipper]

Yes.

The water in the system expands when hot and because it's in a closed system the system pressure will rise. Any over pressure, in excess of 3.0bar (usually) is protected by a pressure relief valve.

 

[bobajob100]

Thanks tipper that helps as it usually ran at 1.5, only I have the same problem ongoing with my 6 month old Ariston that other people seem to have with the dropping pressure. I have together with the installer done most of the checks that have been suggested ie overflow pipe etc and have only found one thing that comes under suspicion, that is one radiator has a couple of drips when the rad is been cold. Would this small amount be enough to cause this. I appreciate there would be some evapouration when the heating is on. What do you think