Worcester boiler won't repressurise

rockm

Hi
I've got a Worcester boiler which started getting a bit temperamental as the pressure gauge had dropped right down to the bottom. I had a plumber come out and he replaced a few parts but it hasn't solved the problem. After repressurising the boiler, the pressure would drop right back to zero again with 24hrs. At the moment it won't repressurise at all & a couple of the radiators in my flat need bleeding constantly as so much air is building up. I've already paid over £300 and I don't know whether it's worth getting another plumber out or just buying a new boiler. Has anyone had any similar problems?
Grateful for any advice. Thanks!!

kizzie_nikita

Our boiler (same brand) has been at 0 pressure for weeks! Wasn't until i rang my dad and he explained to me how to bump it back up to where it was needed. I assume you've opened the tap yourself to push the pressure back up?

rokel

Tell me about it!! have Worcester 24CDi (old I know). had pressure problems, called our regular service engineer. Had new gas valve, then new heat exchanger - total cost over £400. nothing seemed to make any difference. had to re-pressurise every couple of days and have been doing that for about a month. Decided to get some quotes for new boilerand arranged for engineer visits - and guess what the silly boiler has been working perfectly for over a week - stays at 1 when not on and no higher than 1 and half when in use. Why?? who knows but long may it continue. and the moral of the story? - try threatening it with a replacement! But, does anyone have any other ideas as to why the boiler seems to have 'righted' itself? I didn't know it could.

rockm

Yes we've been repressurising ourselves using the valve underneath the boiler to get it to the right pressure but within 24hrs it drops. The last 2 times we've tried to repressurise, you can hear the air but the pressure gauge doesn't move
The thing is, the heating and hot water are working fine (other than having to constantly bleed radiators) so I don't know whether to just hold out or get a new boiler

rockm

Spoke too soon. Bled the radiator and now the heating has gone off & no hot water :-(

rokel

should be water you hear when you turn the valve under the boiler- at least that's what we hear. We use the key anti clockwise first then turn the small valve clockwise. our gauge then climbs quickly at first then slows, as it reaches 2 we turn off the small valve then the key. Usually get some drips of water as you take key out. We are crossing our fingers that ours is ok now. good luck.

oldskoo1

I'm not a gas engineer but replacing a gas valve and heat exchanger for a pressure problem surely is the completely wrong place to be looking and sounds like you have been a quick money fix for a local engineer.

There would be a pressure release valve leading to the outside, their should be a copper pipe coming out of the outside wall pointing back towards the house. Can you detect if there is water dripping from this. Likely to be a constant drip.

If you have turned the pressure release valve or it has activated itself at around 3bar pressure then it might not reseal and cause a constant leak causing the system to loose pressure.

It could also be the expansion vessel but i dont recommend trying to re-pressurise yourself. Especially if its in the boiler and you need to remove combustion seals. You need to call a proper gas engineer for that.

Even if it's the red dome looking thing next to your hot water cyclinder. They need to pressurise back to x bar properly with a proper guage. But firstly the engineer would need to check for leaks on the seal.

Only other thing i can think of is leaks in the pipe work somewhere but i would have thought you would notice a collection of water somewhere around the house.

1 last thing, do you have isolation valves under your boiler, on the pipework? You could try isolating the boiler and see if the pressure still drops. Re-pressurise back to 1.5bar and isolate, see if it still drops, then you know the problem is with the boiler and not a leak elsewhere.

If you dont know how to isolate or what it means dont try it and dont touch the yellow pipe.

southcoastrgi

goodness me you three !!!!!!!!

the first thing you both need to check is that the prv isn't leaking, tie a freezer bag over the copper pipe that goes outside & see if you get water in it, if you do you need a new prv.

where on earth did you find a "heating engineer" that thought he could cure your WATER pressure prob by changing the gas valve, unless you could see a leak within the boiler then the heat exchanger didn't need replacing either.

you need to turn the small valve anti-clockwise (the same way you turn your taps on) to fill & clockwise to shut off, this of course should be done when the boiler isn't running.

kizzie DO NOT run your WB at zero alot of them don't have a low pressure cut off switch & you WILL knacker the heat exchanger.

if you get anymore probs get a heating engineer that knows what he is doing & not the one that rokel has been using.

southcoastrgi

snap oldskoo1 but you got in first lol

brewerdave

When my daughter's boiler kept losing pressure and we got a build up of air in the bathroom radiator, we had the plumber/service engineer in 3 or 4 times (fortunately free as it was still under warranty!!) - finally the manufacturer's man stripped down the final stage heat exchanger -found that it had a pinhole leak -so the recirculating water was "bleeding off" into the waste condensate which was plumbed direct into the foul sewer outlet from the bathroom -so out of sight ,out of mind. Any air in the system was being introduced when we topped up -and the air bleed valve was sticking!!

rockm

Thanks for all your advice. I managed to repressurise the boiler tonight so I have heating and hot water...for now. The pressure gauge has already started dropping slowly so there has to be a leak somewhere. Called a plumber to come out but they wanted to charge £80 + VAT per half hour for labour and they couldn't come out today so I cancelled them.