Potterton Puma 80

[sam775]

I’m having a few problems with my boiler,
Problem (1) I am not getting a proper HW supply, the water is running at normal pressure but is only just warm, because the flame on the boiler does not go to full flame but stays low, if I turn the flow down at the tap to 1 pint / 10 seconds the water is hot (but this would take days to run a bath)
Problem (2) probably connected to problem (1).
When the CH comes on it is supposed to go to full flame after 2 minutes but never does and the pump is running OK but does not manage to get the heat to the last radiator in the system, (have bled this radiator which eventually gets it hot but back cold next time).
I would most grateful if any of you Potterton Guru’s can give me a clue.

 

[ChrisR]

Hmm - gas valve probably , though could be sensor, gas supply...

 

[Agile]

He does not say if this is the electronic or permanent pilot and the diagnosis would point to different things in each case.

If electronic I would first check gas pressure at inlet as this is probably restricted.

If PP then that is unlikely as it would be expected to put out the pilot.

If gas pressure is OK then I would check volts to the mod coil.

If thats OK then the gas valve settings could be way out as a result of an uninformed fiddler. I see that every couple of months!

Apart from checking volts on the mod coil everything else should be done by a competent CORGI so for safety reasons I cannot give you detailed instructions.

Tony

 

[sam775]

It is the Puma 80 not 80e electronic, have had the Gas input pressure tested and that is as it was before and no one has touched or fiddled with the Gas valve.

 

[Agile]

If gas pressure is OK then I would check volts to the mod coil.

 

[baxpoti]

Hmm - gas valve probably , though could be sensor, gas supply...

Mod board...

 

[sam775]

Thanks for suggestions, will borrow a meter tomorrow and check voltage. Will be back with my findings tomorrow.

 

[sam775]

Have now checked voltage of Transformer and voltage very close to 24v, but have tried checking voltage on Red and Black wires on Gas Modulating Valve with and without hot water running and no voltage present, does this indicate a faulty Control Board or Faulty Gas Valve.

Your thoughts would be much appreciated, thank you.

 

[sam775]

After a lot of checking I finally decided to take out the PCB board for inspection and found a dry solder joint on back of board, resoldered joint put back board and hey presto everything works again.

So BAXPOTI gets the prize this time he was spot on.

Thanks for help and suggestions, can now have a nice hot bath.

 

[Soggy_weetabix]

So BAXPOTI gets the prize this time he was spot on.

Of course he does!

He is an expert at diagnosing a faulty PCB. They rarely fail on this model (or any other Baxi/Potterton boilers)



Well done