It's suddenly developed a fault. It heats the water in the cylinder
but not the radiators. The boiler only comes on if the HW switch
is on - however even then the CH switch is useless in activating
radiator heating. Last year it stopped working and I rectified it
by replacing the PCB with a reconditioned unit. It has been working
fine since then until this happened. If anyone has any advice apart
from getting a combi, I would much appreciate it.

Pat, December 2007

Thanks for the response. Only problem is I don't know where the
mid-position valve is located in my house . Any clues ???

Cheers

Pat

Pat, December 2007

faulty mid position valve - probably the synchron motor inside. does the valve move over when you turn the heating on?

Paul the gas man, December 2007