pressure issue on combi boiler

[aeu99217]

Hi,

My boiler had been leaking for a while and thus losing pressure, but since it was only a little to begin with I lived with it and just checked the pressure and topped it up every now and then. However, at the weekend it no longer held any pressure and any water i put in simply came out of the pressure relief valve. Today i have replaced the valve and the boiler seems to be working fine. However, the pressure slowly rises until it reaches about 3 bar when i release some water to bring it down. On the boiler it says to maintain pressure between 1 and 1.5.

When i replaced the valve, this is what i did,

switched off electrics, closed all pipes, took old valve off, replaced with new valve, switched all pipes back on, switched electrics on.

Does anyone have any ideas about why this is happening?
Is it because i drained the boiler and then started it back up again?

Any help would be greatly appreciated.

Thanks.

 

[glasgowgas]

your expansion vessel needs re charged/replaced

see wiki at top of page

 

[aeu99217]

Hi,

Just finished re-charging the expansion vessel and its worked a treat.

Thanks for your help, oh and, 'mon the Gers!

In case anyone else is looking for instructions on how to recharge the expansion vessel, here's the two pages i found:

http://www.howtomendit.com/answers.php?id=68441

http://www.ultimatehandyman.co.uk/forum1/megaflow-primary-flow-leakage-problem-t6663.html