CH gas valve clicking

the boiler has been playing up a bit today. When the room stat is calling for heat then everything is fine, the boiler goes on and off as normal. If the rooms are warm enough and the CH is just keeping the HW hot, is seems to be struggling to light. As the boiler is about to light up, the gas valve will click a few times, sometimes light and quickly go out, then finally get going. It also only seems to do this when the boiler is on the LOW setting, switching to HIGH seems to stop the problem.
I am guessing this might be the LOW temp stat inside the boiler on its way out? Does that sound about right?
cheers
Dave.
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On Tue, 23 Dec 2003 16:31:08 +0000, a wrote:

Almost certinly you have a low tech boiler probably something like an Ideal/Stelrad Elan or Thorn/Myson Apollo? These have a couple of simple on off thermostats for control. Quite likely one or both is on the blink and make an intermittent contact as they close.
The themrostats are available from heating spares outlets.
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Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
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It is a thorn apollo - very low tech :o)
Can these stats lose their hysteresis (they are simple bimetallic things arent they?) or just become worn/pitted due to the constant switching at high voltage?
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On Tue, 23 Dec 2003 22:32:38 +0000, a wrote:

Yep they can go o/c s/c or intermittent or dodgy.
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Ed Sirett - Property maintainer and registered gas fitter.
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