Hi, I have a Chaffoteaux et Maury Brittony Combi 80 boiler.
The central heating was working fine but during the past week the domestic hot water suddenly started running cold. Then it came through hot again. Now it's running cold again.
I pulled out the main heat exchanger, wondering if there might be a blockage in there. There wasn't. I put it back.
My local plumbing shop said it was probably the 3-way diverter valve that wasn't working. I found that valve and removed the brass thing that plugs into the top with a watertight o-ring seal. I cleaned up the dirty end, thinking that the fault might be due to a bad electrical contact there. (I wasn;t sure how the thing works, but thought there may be a plunger inside that rises to touch the brass thing when the water pressure rises. I replaced it after cleaning.
I opened up the cold water inlet again and switched the boiler on. Now it doesn't fire up at all! Not even for the central heating. The fan comes on, but no flame. Anyone help me with a diagnosis?
Thank you
Dave£