In article ,
raden writes:
In message , Neal
Harwood writes
I have a Potterton Profile 50e boiler, and lately the (thermal?)
cut-out has started tripping. This results in the pump going
continuously, but no hot water.
It happily resets manually, and starts up again.
It seems to trip 4/5 times a week, at different times/conditions - no
obvious pattern.

Any ideas?

The impeller of the pump hasn't broken off the shaft has it ?

or as happened to a friend of mine, the blades had all fallen
off the impeller (and were nowhere to be found).

--
Andrew Gabriel