Overpressurised combi boiler

vasseur

I noticed the pressure was quite low on my boiler the other morning so re-pressurised it (only for a few seconds) and the needle shot right round to about 3.5 bar. I've tried bleeding the radiators loads but nothing seems to reduce the pressure very much. It's still just over 3 bar.

I've now noticed that there is a sort of tap on the side of my house that looks like it comes from the boiler that is dripping loads of water. Is this connected to it? I can hear it splashing all over the patio...I hadn't noticed before because of all the rain.

Any ideas anyone? Sorry to be such a dunce about this - have only lived in this house a couple of months and am not very familiar with this boiler yet - it's a Worcester 24i Junior Combi boiler.

BlueC

The thing on the outside that is dripping is the pressure relief. It sounds to me like you didn't close off the filling loop valve(s) properly when you added the extra pressure, so water is still entering the system, over-pressurising it, and the excess water is escaping through the relief valve as it is supposed to.

Check the filling loop valves are actually fully closed. If they are then it could be a faulty valve. Ours recently went, same symptoms as yours - needed a new filling loop which cost £95 for the part plus labour.

thefishdude

when the pressure is to high, it is released through the overflow wich is what you are talking about. pressure in the boiler should allways be checked when it is cold as it naturally goes up as the water is heated.

vasseur

Thanks so much for your quick reply - I've just done some extra research (thank you also google) and have just found out exactly that. Have just rung my plumber and he has confirmed the valve's probably gone.

Hate when technical things like this happen!

Thanks again...

macman

£95 for a filling loop, plus labour?! About £15 at my local plumbing merchant...
If the PRV has lifted due to overpressure, then you may need to replace it as well-it will normally lift at about 3 bar.

DevCoder

I thought filling loops were not meant to be left connected under water regulations?

Ectophile

krisdorey wrote: »

I thought filling loops were not meant to be left connected under water regulations?

They are not. But nobody actually disconnects them. That's why they put a valve on each end, just to be on the safe side.

BlueC

macman wrote: »

£95 for a filling loop, plus labour?! About £15 at my local plumbing merchant...
If the PRV has lifted due to overpressure, then you may need to replace it as well-it will normally lift at about 3 bar.

Show me where you can buy the entire valve assembly which includes 3 valves and loop for a Vaillant boiler for £15. The know-alls on here do my head in.

southcoastrgi

BlueC wrote: »

Show me where you can buy the entire valve assembly which includes 3 valves and loop for a Vaillant boiler for £15. The know-alls on here do my head in.

very true apart from the fact it's a WB 24i Junior & not a Vaillant

Lgas

Hmm do you fill it via the usual Worcester method (plastic key) or have they fitted an external filling loop? Don't often see the internal filling loops passing on them (or maybe i've just been lucky),

vasseur

Thanks everyone. It's all sorted now. I do leave the filling loop connected - I asked my plumber if that was OK and he said it was. The problem was actually me though! I hadn't tightened the screw enough on the filling loop so it was keeping the pressure up It doesn't look like the PRV has gone as the plumber fiddled with it and the water that was peeing out of the tap stopped.

I know for the future just to repressurise it slowly and make sure the screw is exactly parallel.