Baxi solo 2pf turns on off on off repeatedly

[SlimD]

When it starts up the fan comes on for half a second then off, then on, off, on, etc...
Air pressure switch seems to be making. Both overheat & thermostat ok
Potentiometer?

 

[AMGasServices]

Is the termistor connected and working fine?

 

[SlimD]

Is the termistor connected and working fine?

Yes. Seems it was a loose connection somewhere on either the board or the potentiometer. I had it all out to check it and when I put it all back it all started working normally. Bloody electrics!

 

[Elgordo]

That’ll be the board , it’s usually the relay that controls the fan kicking in and out because of a dry joint - if you pull out the board and turn it upside down you can see it sparking in sympathy . Resolder the joint or if it’s badly burnt replace.

 

[SlimD]

That’ll be the board , it’s usually the relay that controls the fan kicking in and out because of a dry joint - if you pull out the board and turn it upside down you can see it sparking in sympathy . Resolder the joint or if it’s badly burnt replace.

Thanks I’ll remember that if I get called back to it