Combi Boiler Pressures

cajef

Juat had a look in the manual for my Worcester/Bosch combi boiler, it states 'maximum permissable operating pressure 2.5 bar'

calleyw

cajef wrote: »

Juat had a look in the manual for my Worcester/Bosch combi boiler, it states 'maximum permissable operating pressure 2.5 bar'

I would have looked at mine but can't find it, I did try looking the model on line but it just says its a HE model!!!

Yours

Calley

Seronera

OK people, its a simple fix for an engineer. Boiler must be cold. Turn off electric to boiler. Isolate flow and return at boiler, Drain boiler using boiler drain..(not Pressure Relief Valve) (no need to drain the whole heating system). Leave boiler drain open with bucket underneath and drain tube into it. Fix tyre pump to Expansion vessel valve and pump until gauge on tyre pump reads 1 bar (ignore the boiler pressure gauge for now). lots of water will come out into the bucket. When the pump gauge reads a steady 1 bar and the boiler gauge is on zero....the job is nearly done. Close boiler drain, open flow and return and only then..pressurise the boiler gauge to 1 bar....then test and top up if neccessary back to 1 bar.

Do not go near the Pressure Relief Valve on a Worcester as they place them deliberately in an impossible place to get out.

Leave all this to the engineer. If you are unfamiliar and try it, you will mess up. Your mess up will be costly most likely. My only reason for posting the method is that just pumping up the expansion vessel is NOT the correct procedure without draining the boiler first

calleyw

Seronera wrote: »

OK people, its a simple fix for an engineer. Boiler must be cold. Turn off electric to boiler. Isolate flow and return at boiler, Drain boiler using boiler drain..(not Pressure Relief Valve) (no need to drain the whole heating system). Leave boiler drain open with bucket underneath and drain tube into it. Fix tyre pump to Expansion vessel valve and pump until gauge on tyre pump reads 1 bar (ignore the boiler pressure gauge for now). lots of water will come out into the bucket. When the pump gauge reads a steady 1 bar and the boiler gauge is on zero....the job is nearly done. Close boiler drain, open flow and return and only then..pressurise the boiler gauge to 1 bar....then test and top up if neccessary back to 1 bar.

Do not go near the Pressure Relief Valve on a Worcester as they place them deliberately in an impossible place to get out.

Leave all this to the engineer. If you are unfamiliar and try it, you will mess up. Your mess up will be costly most likely. My only reason for posting the method is that just pumping up the expansion vessel is NOT the correct procedure without draining the boiler first

I wont be touching it. I will try and get someone in to have a look in the next few days.

Rang someone yesterday afternoon and not got back to me.

I might pop along and see my neighbour. I know this sounds strange but last time he did some work for me he never sent me a bill. I asked a couple of times but to no avail and now I am just feel uncomfortable asking him again.

Yours

Calley

Seronera

calleyw wrote: »

I wont be touching it. I will try and get someone in to have a look in the next few days.

Rang someone yesterday afternoon and not got back to me.

I might pop along and see my neighbour. I know this sounds strange but last time he did some work for me he never sent me a bill. I asked a couple of times but to no avail and now I am just feel uncomfortable asking him again.

Yours

Calley

Take him a bottle of decent Malt Whisky as a thankyou..(assuming he likes it and is not an alcoholic or teetotal..usual disclaimers etc).

Please note: This is highly technical advice from an expert in the field:D

JohnB47

Seronera wrote: »

OK people, its a simple fix for an engineer. Boiler must be cold. Turn off electric to boiler. Isolate flow and return at boiler, Drain boiler using boiler drain..(not Pressure Relief Valve) (no need to drain the whole heating system). Leave boiler drain open with bucket underneath and drain tube into it. Fix tyre pump to Expansion vessel valve and pump until gauge on tyre pump reads 1 bar (ignore the boiler pressure gauge for now). lots of water will come out into the bucket. When the pump gauge reads a steady 1 bar and the boiler gauge is on zero....the job is nearly done. Close boiler drain, open flow and return and only then..pressurise the boiler gauge to 1 bar....then test and top up if neccessary back to 1 bar.

Do not go near the Pressure Relief Valve on a Worcester as they place them deliberately in an impossible place to get out.

Leave all this to the engineer. If you are unfamiliar and try it, you will mess up. Your mess up will be costly most likely. My only reason for posting the method is that just pumping up the expansion vessel is NOT the correct procedure without draining the boiler first

I followed similar instructions, from another 'diy' site and repressurised my WB28si. Was easier than I thought and boiler is working great now. Luckily it hadn't popped the PRV.