Vaillant ecoTEC 828 pump starts with cold water tap?
When I turn on the cold water taps everything is fine until I turn the tap OFF. Then the pump (not the burner) on my Vaillant ecoTEC 828 starts and goes off after about 15 secs. If I flush the loo or use the cold water basin tap this does not occur - only applies to cold water taps in kitchen and on the bath. What could cause this ? The boiler has just beeen resited.
Carefree - thank you very much indeed for your reply -its much appreciated and what you say makes perfect sense. I'm sure this will enable me to solve the problem.
Tim Goadby
November 2011
Most likely, a 'dead leg' in the hot/cold water system (a length of pipe running to a dead end), this will cause the aqua sensor to spin as the dead leg re-pressurizes after use thereby bring the pump in to life.
Find and cut off the dead leg, or alternatively, fit a non-return valve on the cold water inlet to the boiler.
Carefree
November 2011
Automatic Answer
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