Potterton Puma Problem !

[Chris B]

Hi,

This is my first post in this really excellent forum - I hope somebody can help me!

The problem is with a 7 year old Potterton Puma, regularly serviced and maintained.

The boiler fires up without any problem. However, every time the main burner shuts down after running for more than a few seconds, the pilot burner flame goes out too! There's a loud click when this happens. (Maybe it always clicked and I just didn't notice it before).

The pilot burner won't relight for a minute or so, but then it can be relit and normal service is resumed until the next burner shutdown - when the pilot burner goes out again etc.

I've cleaned the pilot jet. It normally lights 1st time on the button and it's burning according to Potterton's specs.

Possible clue... I've noticed that if I let the main burner light for just a few seconds and then shut it down by switching to standby, the pilot burner stays alight. I'm wondering if the problem is being caused by an overheat condition shutting off the gas supply to both the main burner and the pilot burner. Can somebody please tell me if this can happen on a Potterton Puma (ie - would the gas supply to the pilot be shut off too). The pilot seems definitely not to be blowing out, it seems that the gas supply is being interrupted when the main burner shuts down.

Any advice will be welcome. I'll probably have to call in my CORGI guy, but I just wanted a second opinion before I pick up the phone.

Many thanks in advance,

Chris

 

[ChrisR]

Yes an overheat shuts the pilot off. If it works for a while on HW drawoff it's probably a dead pump .

 

[Chris B]

Okay, that's great. Thanks for the info. Good job it's summer and I don't need the CH !!

Chris B

 

[ChrisR]

DOn't leave it till autumn - overheating will also happen on HW and it's not good for it. New pump £90 ish + fitting.

 

[Chris B]

No, I won't leave it until autumn - I've shut the boiler down completely and my corgi guy is going to fix it first thing on Monday morning (tomorrow).

I wonder if, after 7 years in service, it's time to start thinking about a replacement (I mean the boiler, not the corgi man). Anyone know the life expectancy of these Potterton Pumas?

 

[ChrisR]

COuld be the overrun stat has packed up.

Pumas seem to go on for a fair while - not many being scrapped yet, but a number of things do go wrong on them. Pcb, pumps, flow switch, diverter valve all seem too frequent. Perforated heat exchangers happen, and Breezer's (?) scaled up badly.

I'd bear with it though for a few years.