overheating problem on Baxi

[hotncold]

Have a friend with a problem on a Baxi Solo 3 PFL70.
Overheat light comes on, when reset boiler is Ok again, problem started a few weeks ago and happens about once a week.
Fan replaced about 3 months ago.
Unvented system, name on tank is AIS OSO.

Any thoughts anyone

Thanks

 

[Agile]

It may be genuinely overheating and only a thermal time recording might show that!

One might ask if the pump over run is correctly connected and operating.

PCB faults often seem to give that result though.

Tony

 

[hotncold]

Tony
Thanks for your comments.
If it is genuinely overheating what could cause that?
Also , it could be the stat?

 

[baxpoti]

Check for correct by-pass arrangement, it may have been shut off accidentally.


Pump should run on for approx 8 mins after demand has ceased.