Potterton 80 problem-red LED always on

[daj12a]

I have a Potterton 80 combi boiler which has always had the problem with the hot water still heating (red LED on the PCB on) though all the taps are off-quickly opening and closing a tap would do the trick. Now the problem has worsened with the LED on all the time- have had to put the boiler on standby. The PCB has always fizzed and crackled in operation (especially around the relays on the middle of the board). Should I-
1) Replace the PCB, part no 21-18601?
2) Try and fix the PCB?
3) Blame the D.H.W. Flow Switch instead (and can I test this)?
4) Ditch the whole piece of junk?
Many thanks, Dave J

 

[Agile]

Its the DHW flow switch sticking !

The PCB is unreliable but fix the DHW before considering replacing the PCB.

Your boiler is somewhat unreliable but there are plenty still in use and easy to repair for those who understand them.

Tony

 

[daj12a]

Thanks for the reply, Tony. By "fix the DHW" do you mean simply replace it, or is there any fault-finding/repair I can do? Cheers..Dave J

 

[Agile]

As I dont know how yours has failed then I cannot advise apart from saying replace it as thats a bound to fix it solution.

Tony

 

[daj12a]

Tony-I took apart the PCB assembly to get at the switch, worried it a bit and applied some WD40. Got it clicking like a good 'un in response to the water pressure, and re-assembled. All seems OK..fingers crossed!
Many thanks for your help..Dave J

 

[geoff@cetltd]

The PCB has always fizzed and crackled in operation (especially around the relays on the middle of the boardJ

Sort out the pcb

if the connector pins on the pcb start coming loose, ultimately the pcb can catch fire in a major way

 

[Trance Nation]

Yes do that as soon as. Ive seen them melt the connectors away loads of times, but actually seen one that had set fire to the kitchen earlier this week.

Scary stuff. Dont let that alarm u though !

 

[geoff@cetltd]

In the case of a Puma / Combi 80, it would be with a manufacturers original part, as well you know

Potterton's flow soldering does not give sufficient mechanical strength to the connectors - which is why we always reflow the solder on the connector pins

 

[geoff@cetltd]

WHat happened to Agile's post that I was replying to ?

It's disappeared