Hi, why is the overheat stat popping? is it because the water is getting too hot and the overheat safety button popping out? how hot do your rads/pipework get? have you heard any boiling/kettling noises before the overheat stat pops? It's quite possible your control thermostat has gone so the burner comes on and keeps going (uncontrolled) until the system gets too hot and cuts out. I've just fixed one on a Profile 40 and it's running sweet again. I got a control thermostat from PTS for about £15 + vat. You could call the Potterton technical helpline with the exact symptoms - they're helpful. A new pcb may well be needed as Potterton have had problems with these. Try the stat first in my opinion.
MC Heating, February 2011
