Baxi Solo 3 Boiler clicking relay after pump overrun

[MARTINHOG]

Hello, I have a problem with my Baxi Solo 3. The sysytem its self is working correctly, the problem appears after the boiler shuts down;the pump runs for another 10 minutes as it should, however when it is due to switch off, the relay controlling the pump "pulses" around once per second, this causes the pump to pulse, however the time between the pulses slowly increases until it switches off properley after around 30 seconds.I am experienced in fault finding. I examined the PCB and re-made a few dry joints, and did some cold checks around the pump relay but with no success.I don't wont to buy a PCB !. All help is appreciated.

[Ed Sirett]

There is a time not to reinvent the wheel and this may be it. If you really want to diagnose the electronics yourself and your time is worthless then sci.electronics.repair FAQs might help.

otherwise... This is some sort of fault with the PCB. I expect raden who is cetltd.com may be able to help. I believe pump (over)running problems with this PCB are 'normal'.

[MARTINHOG]

Hi,Discovered that capacitors C12 and C13 (100uF) had failed and that C20 was about to die. Changed all 3 and now it works a treat !.

Only do this job if you are experienced in PCB component replacement, the PCB is at mains potential.

[Roger Mills]

You surely didn't do this in situ, with the boiler/PCB powered up?!