heating wont work boiler comes on with hot water but wont fire on the heating any suggestion

juniper, October 2008

Hi Juniper.
I had a similar problem with my wocester bosch combi, but traced it down to the water divertor valve.
I didnt have to take the whole valve out, just the solenoid coil which was open circuit and hence not working. I found a replacement on the internet and now heating is working fine

trevor, October 2008

Depends on type of system
If gravity suspect pump
If pump primary mid position motor suspect motor

a, October 2008