Hello
I have a Potterton Netaheat boiler. In spite of putting in a new pump and desludging the system, the expansion tank is collecting boiling water which now and then spots out from the overflow pipe. I think the thermostat on the boiler is gone. ? Can this be mended? Any help welcome

H.P., February 2010

I recently had the same problem with boiling water going into the expenasion tank and overflow. British Gas engineer suggested pump and or sludge which I didnt believe to be the cause. After several more call outs I convinced the engineer to fit a new boiler termostat and that fixed the problem.

byteguy, February 2010