Glow worm Compact 100e

[ifonlyiknew]

I have a glow worm compact 100e 3 yrs old, yesterday i had no heating but hw was ok, plumber rectified problem stating the part the hot water micro switch attaches to seemed to be stuck, he released and all ok.

Today i have heating but no hot water, plumber came back and replaced the hot water micro switch, all seemed ok.

Went to run a bath and the hw comes on hot for approx 30secs then goes cold, the hw light on the boiler is on even when the water goes cold, when i turn hot tap off the light switches to heating as normal.

Could anyone give me any suggestions as to what the problem might be?? any help would be appreciated, cant stand boiling saucepans for hw!! thanx

 

[kevplumb]

could try taking the head off the divertere valve run the tap and see if it moves