Boiler wont stay on


Hi All Ive got a standard gas central heating system, Ideal boiler, Grundfoss pump, Honeywell roomstat,10 rads. Older system, had to have it flushed recently. This weekend, we drained and refilled the system, but now the boiler wont stay on. When the stat is clicked, you can hear the pump click on, and off when it clicks off, so I dont think its the stat. The pump appears to be spinning too, you can see the mini whirlpool, when you open the brass screw, so not the pump? Could it be anything else?
Any ideas to try....please help...desperate and cant afford a plumber till next month! Thanks Maskie
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If the boiler wont stay on and you have to relight the pilot then the most likely cause is the flame failure detection thermocouple ...about a fiver from your local plumber...but remove the old thermocouple first to compare because tere are many types and these supposed universal thrmocouples are not as universal as they would have you believe!...least they didnt fit my Vulcan Continental.
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Sorry, when I said it wont stay on, I meant to exppin that it switches itslef off. The pilot light stays lit, its some wort of switching or pressure fault. Thanks maskie
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You drained and refilled the system this weekend.
Your problem is most likely to be air in the boiler/system. Can be a bugger sometimes trying to shift it. Check all manual/automatic vents in the system. Run with the pump vent screw removed.
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