Hi , I wonder if you can help we have a baxi that keeps the water hot but will not heat the CH, it keeps firing, makes like s fizzling noise then 30 seconds later it cuts out. We have had the pump replaced as before it was warming up the upstairs radiators but not the downstairs ones. Any Idea's cause its costing me an arm and a leg to get sorted

Mo, November 2008

If the pump is running then there can be a few problems.Check the pressure on the boiler to start and bleed the rads. make sure the lock shealds are turned on and the trvs.
does the boiler fire up then you turn the heating temp up on the boiler front if not check the diverter valve! are the pins working?? they should open and close on the CH and the DHW when turned on.
Check the pipe work for cross over or blockage from dirt or old age.

How old is the boiler as it may need changing.

good luck.

mick

mick brown, November 2008