Potterton Combo 100 (PUMA) Lockout

[Parnechris]

Hi All, the above boiler in my flat has started to play up. It is about 5 years old and has been fine up to now. The problem is it locks out after being on for a short while due to I think overheating. Also once on, it won't turn off even when you turn down the thermostat. I have had a guy look at it and he says I need a new pcb and a new heat exchanger or a new boiler.

Anyone out there know if this is the case or can offer any assistance?

 

[Gasguru]

When does it lockout...with hot water or heating or both.

When does it not shut off..after a hot water draw off?

 

[Parnechris]

It locks out when you use the hot water and it won't turn off automatically once the heating is on.

 

[Gasman28]

Normal fault would be the microswitch located on the DHW flow switch.

 

[Parnechris]

Is that something I can get and replaceor is it an engineer job?

 

[Gasguru]

Pop off front cover...when tap is open red LED (middle right on circuit board) should be on and go off immediately when tap is closed.

 

[Parnechris]

Thanks for that. I will check it out. Do you think the guy who took a look at it is talking crap about the PCB and heat exchanger needing replacing?

 

[Agile]

He clearly knows nothing about boilers!

He is trying to frighten you into having him fit a new boiler.

The Puma is a perfectly repairable boiler.

We would probably charge about £84-£124 depending on exactly which part has failed.

It might just need an adjustment!

Tony

 

[Parnechris]

Have you got a number I can reach you on and maybe we can get it fixed. Thanks Chris

 

[superdupergasman]

We would probably charge about £84-£124 depending on exactly which part has failed.

Tony

Bargain..... everone call Tony when the wax divertor capsule fails!!!


Seriously.... the water section can leak on these causing the microswitch
to rust up sticking on thus keeping everything on as the others have said.

Further to this...if the pump sticks on these boilers which they are also bad for it...the boiler overheats, this cuts the power to the gas valve, the boiler tries to ignite and then locks out too

BG will do a fixed price repair including parts for £167 - £200 depending where you are located

 

[Agile]

Bargain..... everone call Tony when the wax divertor capsule fails!!!

Further to this...if the pump sticks on these boilers which they are also bad for it...the boiler overheats, this cuts the power to the gas valve, the boiler tries to ignite and then locks out too

The example figures I listed were only in respect of a stuck dHW demand switch. A waxstat/diverter valve would be more!

That description of what happens with a stuck pump is not quite correct.

On the electronic model the o/h stat causes the PCB to go into lockout mode lighting the lockout light and preventing the ignition sequence from proceeding. The o/h stat is not connected to the gas valve.

Tony

 

[superdupergasman]

That description of what happens with a stuck pump is not quite correct.

On the electronic model the o/h stat causes the PCB to go into lockout mode lighting the lockout light and preventing the ignition sequence from proceeding. The o/h stat is not connected to the gas valve.

Tony

I stood infront of one doing this the other day tony, sparking but no power to gas valve which lead me to think the sequence board was goosed until I
did some further research.

They are an interesting boiler with funny quirks!

 

[Parnechris]

Thanks for all the advise. Would anyone like to have a go a sorting it for me. Regards Chris