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Apr 27, 2025
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Hi all,

I have what I will admit to being an old combi boiler in the house ( Potterton Performa ). It has a strange problem, when the heating is on the hot water comes through really quickly, but when the heating is off it takes an age, as in a whole washing up bowl full of cold before hot starts coming through. If I look at the boiler and start the hot tap, it almost seems like the the boiler isn't sensing the need for the water and takes an age for the burner to fire up, you can hear the pump running and moving the water but the burner doesn't kick in for around 30 seconds. The boiler has recently had a new diverter valve and a PCB. any ideas?

Miniman
 
Sounds normal

Boiler has to go through it’s sequence of opteration normally around 15-20 seconds then has to heat itself up as it’s cold

Hence the quicker operation when heating as everything is warm / hot
 
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Hi all,

I have what I will admit to being an old combi boiler in the house ( Potterton Performa ). It has a strange problem, when the heating is on the hot water comes through really quickly, but when the heating is off it takes an age, as in a whole washing up bowl full of cold before hot starts coming through. If I look at the boiler and start the hot tap, it almost seems like the the boiler isn't sensing the need for the water and takes an age for the burner to fire up, you can hear the pump running and moving the water but the burner doesn't kick in for around 30 seconds. The boiler has recently had a new diverter valve and a PCB. any ideas?

Miniman
Delay is due to having to heat up from cold. Does it have a preheat function that could be enabled?
 
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Reactions: RBG

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