Boiler pressure rising

[Andy C]

Hi Every one

I am new to this forum, looking for a bit of advice on a Vaillant VCWGB242EH/282EH can anyone help?

The pressure has been sitting at 2.5 bar for a few days now (whether system hot or cooled) with water from overflow, well, flowing.

I changed the pressure release valve but the pressure now sits at 3 bar as before, hot or cool. Not flowing from overflow though now, just dripping.

Wanted to change the DHW expansion vessel but the part sold locally to me wasn't on the boiler to be replaced. The technician at Vaillant who I rang to find out why I couldn't find the part to replace said it was obviously not fitted with one and instead in this case is a big part at the back of the boiler more like a cinema film reel case size.

Anyway, I know 3 bar plus is max so bordering on unsafe, which way should I proceed next. I know I should get a Corgi chap round but I'd like the satisfaction of fixing it myself and money is tight too.

The PRV was a doddle to swap so with a little help I may be able to pull this off.

Thanks in advance!

 

[weargas]

check that your filling loop isn't letting by when in the off position.

 

[Andy C]

Thanks for that tip, seems to have done the job. Sometimes it is the simplest of things!