My pilot light keeps going out, only after water use, shower bath or sink full of water. I can here the gas valve shutting off about 5-10 seconds after the main burners go out. It re-lights straight away, no problem. I've replaced the thermocouple, pilot burner and electrode.
Everything points towards the thermocouple but it's brand new!
I have the same with my potterton puma 100 i changed the thermocouple,no luck.got combi man out to look at it,hecould not find anythink wrong he turned the pump from 2 to 3 (full) and charged me £84 .I replaced the pump 2/3 years ago but not with a potterton one its a single speed one and twice the price of a three speed made by same maker i ran new pump on 2 it made heating quiter.To soon to tell if it worked i will let you know.
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