no hot water, but CH working ok

wheeze

the boiler is working fine, the tank in the airing cupboard is warm but our hot water tap runs hot for about 30s then goes cold.

Just had a plumber out but he cant help as he doesnt touch pressurised systems which is what i have apparently.

So will look for a plumber in this field tomorrow, but anyone have any ideas so I'm not totally in the dark !?

ormus

need more info,
what make/model boiler do you have?

alanobrien

Possibly a duff diverter valve or more likely the valve motor

wheeze

thanks for replying, its a Gloworm Ultimate

Canucklehead

Hi

Maybe you have an unvented hot water cylinder.(this requires a G3 certificate to service/maintain) I can't think of any other reason that anyone would walk away from a sealed heating system.
As above the most likely problem is the sync motor in the motorised valve.
http://www.grahamvideos.co.uk/test%20info%20icon%20jpeg%201/4524098771
This is just to show you the suspect item!
(I wouldn't pay to watch this )
Corgi Guy.

JennyW_2

we've been down this road. Central heating working fine but hot water wasn't so hot, very hit and miss.

We changed the temperature sensor, divertor valve and the heat exchanger and it still didn't work.

In the end we put in a new PCB - works fine now. My brother is a plumber and he said 9 out of 10, it's the PCB when things like this happen.

Canucklehead

JennyW wrote: »

we've been down this road. Central heating working fine but hot water wasn't so hot, very hit and miss.

We changed the temperature sensor, divertor valve and the heat exchanger and it still didn't work.

In the end we put in a new PCB - works fine now. My brother is a plumber and he said 9 out of 10, it's the PCB when things like this happen.

:eek: sounds pricey...the 'replace parts until it finally works' route is not the best route to go...an experienced (and honest) CORGI should have diagnosed the problem quickly by following the fault findfinding procedure outlined in the product manual/quick call to technical support without you have to fork out for unnecessary parts.

Canucklehead

stebiz

I've got a glow worm and had this fault too. After British Gas changed a couple of things it still wasn't working. Then a senior guy called out and advised of a full flush. Apparently the boiler works in the same way as a kettle and all the elements get 'clogged up' with chemicals they add to the drinking water.

I was very, very hesitant to pay the £200 but the guy did it within 2 hours and hey presto fault resolved.

Stebiz

JennyW_2

Canucklehead wrote: »

:eek: sounds pricey...the 'replace parts until it finally works' route is not the best route to go...an experienced (and honest) CORGI should have diagnosed the problem quickly by following the fault findfinding procedure outlined in the product manual/quick call to technical support without you have to fork out for unnecessary parts.

Canucklehead

I work for a mechanical engineering company and we are Corgi registered. We did following the procedure and were given this advice from Potterton tech support.

It was no problem as it didn't cost me anything for the parts so we didn't mind changing the various items.

Plus I did post about the problem a few months back and had various replies all suggesting the same parts above.

Canucklehead

JennyW wrote: »

I work for a mechanical engineering company and we are Corgi registered. We did following the procedure and were given this advice from Potterton tech support.

It was no problem as it didn't cost me anything for the parts so we didn't mind changing the various items.

Plus I did post about the problem a few months back and had various replies all suggesting the same parts above.

Good afternoon: I would say you are in a very fortunate position...many MSERs, as witnessed by various posts on the subject have not had the best luck with boiler repairs and have spent out £££:eek:.... forum members do try to give good advice but it is very difficult to diagnose a boiler fault without actually seeing the deviant appliance in question;)

Hopefully, Wheeze will get back to us with greater detail.

Canucklehead

ukjoel

We had the same prob but the other way round.
Water fine but no heating.
I drained rads and checked pump but in the end got stumped so called British gas.

They spent 20 minutes trying to sell me a £30 a month warranty but in the end got them to come out and fix fault for £168.

Sounds a lot but cheaper than the £360 a year the warranty would have cost and they guaruntee to fix all faults or your money back.

The bloke they sent round has now changed loads of bits in the boiler and is back tomorrow to change a few more. The way I see it I am not paying for his experimenting and doesnt matter how many times he comes round its only going to be £168.