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Boiler heating all day/night

Postby DanDare » Thu Aug 09, 2007 12:02 pm

I have a Worcester 240 combi and it appears to be heating all day, without the pilot light being on.

The boiler casing is hot to the touch, and it seems to have had an impact on the cold taps, which run hot for 10 seconds or so before going cold. This is a new issue. My hot water supply has always been good an is unaffected.

I have my radiators switched off so it doesn't affect the heating in the house.

Can anyone give me any thoughts on what they think the problem could be?

Many thanks

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Postby htg engineer » Sun Aug 12, 2007 8:43 pm

If the pilot light is off then there's no way the boiler can be heating.

Are you sure it has a pilot light ?
is it not electronic ignition ?

The boiler will light if the hot tap is opened, is this why the case of the boiler is hot ?

Isolate the electricity supply to the boiler, as if the case is heating up when heating and water are off, then there must be an electrical fault and risk of fire.

As for the cold water, is it hot or warm ? if its hot then there's a problem with the hot and cold water pipes being crossed or water mixing somehow. If its warm - does the cold mains run alongside or above heating pipes ?
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Postby DanDare » Mon Aug 13, 2007 2:57 pm


Many thanks for your reply. You are of course correct :oops: it does has electronic ignition.

The case is heating up when the hot water switch is engaged - but this never happened to such a degree before, we always just left this switch on to ensure instant hot water but the case always stayed cool-ish. It seems worryingly hot now.

At no point has the main heating been switched on.

When I turn the hot water switch off now the case is fine and I can hear no heating is happening within the boiler, which hopefully rules out the electrical thing - so wondering what the issue is?

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