potterton suprima light sequence

[mikesmorris]

potter ton suprima 80l 12 years old original pcb fully pumped system. Boiler temp setting just over half way. Seemingly random occasional intermittent lockout , also random occasional “knocking”. When working “normally” light sequence is as follows. Programmer on and heat called boiler fires solid green. Boiler temp satisfied stops firing solid red with slow flashing green until fires again red goes out and solid green. Demand satisfied or turned off green stops solid red on. Pump overrun seems correct and pump operation seems correct. Solid red stays on until next call. Very much appreciate if anyone can comment on whether sequence is normal and if not does it indicate either boiler themostat problem or pcb problem (am aware of the Suprima pcb issues). Thank you. Mike

 

[Agile]

I think that is correct.

The random lockouts are typical of a failing PCB!

The bumping may be caused by a sticking pump. Next time check if pump is really running when it occurs.

Tony

 

[muggles]

The light sequence is a bit odd, and could be indicative that it's time for a new PCB

 

[lloyda]

New PCB cured my occasional lockouts and random (very loud) knocking (I'd personally describe it more like a small explosion!). It was a completely different PCB module, not just a like for like replacement.

 

[muggles]

Yep, they're a completely redesigned sealed unit. Still slightly unreliable but a massive improvement over the old ones

 

[mikesmorris]

Thank you agile, lloyda and muggles for helpful input. Is the redesigned pcb the one with reference "PCB UPGRADE KIT 5111603" ?

 

[lloyda]

I've just dug out the paperwork (installation manual) that I received when the PCB was changed, and it is indeed part number 5111603.

Lloyd

 

[mikesmorris]

Thanks for that Lloyd - plan is to talk to it nicely to keep going for the winter and get the pcb changed in the spring! Thanks for yours and everyone's help. Mike