gloworm boiler


Old gloworm swiftflo. Turned the central heating on. Pressure went up to 3bar. When the heating went off it dropped back to 0.3 bar (should be 0.7). Refilled to 0.7 bar and turned on the heating. Back up to 3 bar.
Any ideas on the cause?
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Expansion vessel fault....possibly
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On Fri, 26 Oct 2007 21:55:54 +0100, "johnty"

I can't see any leaks.
Looks like a call for the man.
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Expansion vessel isn't working. It should be half full of air, separated from the water by a diaphram. On the air side, there's a tyre valve which is used to pump it up. Take the cap off and try releasing a little air. If water comes out, the diaphram has split and you need a new expansion vessel. If air or nothing comes out, then you can try pumping it up with a bicycle pump. With the pressure released in the heating system, pump it up to about 0.5 bar (7lb/sq inch). If it leaks out again, it might need a new tyre valve, if it's replacable.
--
Andrew Gabriel
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On 27 Oct 2007 09:02:22 GMT, snipped-for-privacy@cucumber.demon.co.uk (Andrew Gabriel) wrote:

Thanks. I've checked for leaks elsewhere and found none so what you say is probably the fault. Still have to get a man in. My eyesight and health isn't good enough anymore to risk messing with boilers in situ.
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