Hot water fine, but no heat to radiators?

[kevplumb]

put a rag under the pump and undo the big screw inside is the pump motor shaft with a slot in the top try to turn it with a screwdriver
if its not already running
hope that wasnt tooooo tech for you

 

[PEDANTICVINDICTIVEMAN]

Might be worth checking feed expansion tank is full as well.

 

[kevplumb]

howay pedantic read the first post you been asleep

 

[plumbdoctor]

I havn't read all that went before fully, but it's worth mentioning that I have on several occasions over the years come across pumps that have spinning shafts but the impellor has broken free or become clogged with sludge, change the pump!