Old part numbers: :248068, 247394, no need to drain the boiler - its in a dry pocket.
It is likely to be the casing seals or fan proving switch.
Boiler occasionally goes to an overheat lockout.If No then replace PCB Replace the Control Board.Boiler manual PDF If it locks out in the morning it may be the spark electrode that gets damp overnight if it has a hairline crack in it, it will usually recover once it has some voltage put through it, hence it lighting on the.Potterton Netaheat Profile 50e PCB : The part number for replacement is 407677 and you can order it from here.Related UK Appliance Questions, i have high end studio color 575 manual a Worcester 37cdi controlled by Nest.It can also be a pressure sensor switch if expansion vessel is OK and it needs replacement.If it is overheating then I would usually check the system and bypass first, and I would replace the overheat and boiler stat sensors before shelling out for a costly pcb.Gas inlet pressure should be 20 mbar.
As the sound is normal when read more.
Flame goes off once the spark stops.
If there is no green light on check sparking.You will need a multimeter to carry out this test.The proving/air pressure switch is located at the other end of the silicone rubber pipes that connect to the fan outlet.This includes proper testing.If it has gone flat they try pumping it up to the afore mentioned pressure.The DC voltage should be between.5V and.After you have downloaded the manual double click on the download for the manual to open, if you want to save the download right click.
In addition to this ensure ventilation into the room where the boiler is located complies with BS5440 part 2 and of course manufacturer instructions.
Resistance on a thermistor: at a room temperature - 14kOhm at 80C - 2kOhm, if the thermistor's resistance is around 34kOhm at higher temperatures then replace the thermistor.
Follow the full commissioning procedure as detailed in the commissioning section of manufacturer's instructions.