I have a Worcster 280 RSF.This morning heating fired up for 15-30 seconds only.We are getting hot water.I suspect the diverter valve is stuck.Recently the opposite thing happened.Turning on the tap did not produce hot water but the CH flow pipe began to heat up.I have bought a new valve in case but my fitter has been ill and is now snowbound.
I would be grateful for any advice.
I would be grateful for any advice.

