Combi boiler pressure at 3bar

[Pgor68]

Hi all. I have recently drained system, removed all rads and manually flushed them all. Filled system back up, bled all rads and repressurised the system to between 1 and 1.5 bar. The system was off all night waiting for the timer to kick in and when I checked in the morning, before it came on, the pressure had risen to 2 bar. While the heating is on the pressure varies between 2.5 and 3 bar, no higher. I released some pressure from the rads, took the pressure down and once again it rose to 2.5 to no more than 3 bar while the heating is on. Any ideas what the problem could be and is it safe to still use. Thanks in advance.

 

[exedon2]

Assuming it was OK before drain down try removing hose on filling loop to make sure fill valve not passing.

 

[cjg]

wait till cold , then drain/fill to 1bar and see how you go then