PRV leaking

Boiler: Worcester Junior 24

We had the boilerman round to service and sort out some issues with our boiler. We had an external expansion vessel fitted as replacing the original apparently would have been a major hassle and more expensive. Fan was replaced and plate to plate HE was flushed out. After the job was done and he'd gone we later discovered a constant drip coming from the overflow pipe which he said was due to the PRV. Also when I checked the boiler the reading was 3 bar, I believe it's supposed to be between 1.5-2 bar. I did bleed a rad to drop it to 2.5 bar but then it popped back up to 3 bar and it's stayed there.
Our problem is, due to the holidays we're stuffed until he can get back out to us. My question is should this have not been checked before leaving the job, I guess I'm getting a little bit anxious as everytime I go to the bathroom I'm hearing this constant drip drip 24/7 and it's just winding me up.

close the cold water inlet valve to the boiler and if this stops the pressure rising you need a new DHW plate heat exchanger to be fitted by a different engineer than the one you are using

Is the filling loop still connected with its valves not fully closed ? This will allow water into the radiator circuit thus raising the oressure.

Also check that filling loop isn't letting by. Should be disconnected but no one does.

ianmcd said:

close the cold water inlet valve to the boiler and if this stops the pressure rising you need a new DHW plate heat exchanger to be fitted by a different engineer than the one you are using

Click to expand...

Thanks guys for the feedback. Filling loop is closed I can confirm The pressure actually hasn't gone back up to 3 bar my mistake it's about 2.6/2.7 but what I'm going to do is bleed one of the rads to bring the pressure down to 1.5bar and then observe. The boiler is in the attic so to get a proper reading I've got to get up close which I didn't before.

When you say the DHW plate heat exchanger. Do you mean the plate to plate HE? Sorry I'm only a reasonably incompetent DIYer


The work (fitted ext exp vessel & fan as issues with shower fluctuating hot and cold and boiler pressure was dropping, now fixed) was done Thursday and in the evening after he'd gone I texted him about the leak and his response was...

Hi, that'll be the pressure relief valve, when you have expansion vessel issues the pressure relief valve opens and doesn't always reseat, it may sort itself out if not it may need changing

Click to expand...

I have since sent a couple of texts and left a voicemail, Friday lunchtime, with no response. I appreciate people will need time with their families and it being Christmas puts extra pressure on folk and he did advise that he was going to be off over Christmas and after will be away for a week so it looks like the earliest we would now see him is at the middle of the first week of January.

I'm just wondering..

• Is this an issue that he should have foreseen before leaving the job
  
• Is this reasonable behaviour from a plumber after a job has just been done.

I don't want to be unfair to the guy as to my untrained eye he comes across as competent (was recommended by a friend of ours) but I am tbh a bit miffed. I'm quite happy to try and get another plumber in asap and to charge it against his bill but considering it's christmas and it's not an emergency is it really worth it?

When you say the DHW plate heat exchanger. Do you mean the plate to plate HE? Sorry I'm only a reasonably incompetent DIYer

Read more: https://www.diynot.com/diy/threads/prv-leaking.514959/#ixzz5aR6pXpgD.

Yes that is what I mean, it is not a plate to plate heat exchanger, it is a DHW plate heat exchanger or a Plate to water heat exchanger, no plate heats any other plate, I know that term is commonly used but it is completely wrong, disconnect your filling loop which should have been disconnected anyway and see if it still rises

We don't have an external filling loop see below....

Yes thank you for the correction re DHW plate heat exchanger

BTW your link is to this thread?!

just close the plastic valve no3 then remove the key and if the pressure still rises it is the DHW heat exchanger

Well since bringing the boiler pressure down to about 1.5 bar that's made the world of difference. There may still be the odd drip but I didn't stand around outside looking up at the pipe long enough to find out. The pressure doesn't seem to be dropping either so hopefully that's done the trick.