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Potterton Supreme - When cold I need to warm boiler with fan

Postby Colin7777 » Sat Nov 20, 2010 5:37 pm

I know there are many discussions regarding the Potterton range but I can not find the answer to this problem.

During most of the year all is OK but when winter arrives the boiler will not start first thing in the morning. I press the reset a few times but still nothing. This is the second year so I know it is only during the winter.

Then I put a fan heater on blowing towards the right hand side and leave for 5-10 minutes.

Press the reset again and the boiler starts up first time.

I have opened up the unit, had a look at the circuit board and although a few dark marks around where the Diodes join the circuit board, inspecting the board all joints look bright and clean.

The pressure switch is working correctly and as it is a problem only when cold I have ruled out the sensors attached to the outflow pipe. The air temp has been around 6-7 C when it has played up so can not see it is a FROST problem if there are any such sensors ?

The boiler is in the garage and it can get cold in there and I guess the fan heating is solving the problem but I can not work out what the problem is to rectify it.

Will the warm air have any affect on the way the Gas valve works, could it still be the circuit board or is there any other items that I need to look at.

In the manual it says check to see if there is a spark through the viewing window while checking the voltage on the gas valve. Is it safe to remove the outside cover and front insulation panel so I can see if the spark is firing as there is no way to see the spark as the front insulation panel covers it and the viewing window is also on the opersite sie to the ignition, typical Potterton manual.


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Simply Build It

Postby Colin7777 » Wed Nov 24, 2010 10:49 pm

I decide to purchase a refurbished PCB and can now say the boiler has worked for two days now without a problem.

I have looked closer at the old board and can see that diodes D7 and D8 are loose so the track / drty solder joints.

I guess that moisture on the board was causing a high resistance and therefore the board would not work.

Blowing warm air in the area obviously dried the board and the board worked OK.
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