Pumpintermittent fault when hot question...

[jackecole]

Hi

I've heard that an intermittent fault that can occur on a combi / boiler is that a pump can fail when hot - so when tested (cooled down) you can't find the fault! Is this true.... ? If so, how do you find this fault out

 

[petit_pablo]

It can happen yes on any pump.

Run the system hot and observe pump. The clues will be there, noise, overheating etc.

 

[jackecole]

I just wondered why this happens - what causes the pump to slow/fail when hot only?

 

[kevplumb]

windings start to go down to earth when warm