Oil boiler tripping on over temp

[Ballyman]

Hi

I have an oil boiler that's tripping out all the time on the over temp switch. When I press the OT switch back in it starts up again.

The radiators are getting red hot before the boiler trips. I have set the thermostat on the boiler to 60 degrees (from 90) but it doesn't seem to control the temp of the boiler at all and it just keeps heating until it trips.

Any idea what it might be? Is it the thermostat? Everything seems to be working normally in that the radiators at heating it's just that they are getting too hot.

Thanks a mill for the advice.

 

[roker]

Sounds like the normal thermostat has failed allowing the temperature to go up to the over temperature thermostat

 

[jhegarty]

Could be your pump on it's way out.

 

[roker]

If the pump failed, it would cut off on the normal thermostat