Baxi 105 he

[titchandy]

Hi guys gals, a little help would be much appreciated, I went to a baxi 105he yesterday. Not firing for heating or dhw no fault codes flashing. Pump proving pin going in and out constantly which is pulsing the pump but when I activate microswitch it doesn't fire up either. Diverter leaking anyway so will be changing that..when hot tap on Front pin comes out but not proving pin Ideas much appreciated. Having a brain freeze at mo Tia



Reminder - DIY GAS: https://www.diynot.com/diy/threads/diy-gas.8090/

 

[durhamplumber]

Pump proving switch cycling is usually weak pump or hole in small diaphragm.If manual operation of proving switch does nothing,check voltages,continuity of microswitch.Maybe entirely new divertor if leaking anyway.Other than that,thermistors give lots of trouble,but do not fit your symptoms.Could be blockage in thin pipes from divertor,or possibly pcb..