Basic checks:
There is and overheat thermostat attached to the pipework bottom left rear of the boiler (there are 2 low voltage wires attached to it), this is a manual reset.
Is the pump running and the pump micro-switch (above the pump) breaking?
Is the fan running?
Given the limited description of the breakdown, this is the best help that can be achieved.
Carefree, December 2015
