Worcester Bosch 240 CH Problem

[fox146]

When CH is put on boiler fires up, pump works, radiators get hot. After approx 5-10 mins ( when the CH return pipe gets hot ) the boiler goes back to pilot, ie waiting for the circulating water temp to drop. After a few mins the pump stops working and then the boiler fires back up, which results in it over heating and the pressure goes upto 3 bar ( Boiler shuts down including pilot light). After approx 5 more mins the pump starts again.

Any suggestions ?

Marc

 

[cjb1971]

If the pump is getting 240v to it when it stops wrking then faulty pump-if its the board that stops sending the 240v to the pump then the pcb has had it at a guess-its a bit hard to say without doing some tests on it

 

[fox146]

Hi cjb1971,

Thanks for the reply

The pump is being sent 240v all the time, could it be a fault with the pump? why would the pump work to start off with then stop, and then start again approx 5 mins later.

Thanks Marc

 

[gas4you]

Could be the pump bearings seizing at the higher temperature and stopping, then the boiler overheats.