hi there thanks for your reply, there is water in the system,i had a couple of rads fitted a few weeks back after reading on the forums i think it may be an air lock,the boiler is in the attic, also the copper mains water pipe is heating up really hot but the water from the tap does not get over...
can anyone help with my boiler ideal he 30 i have no hot water heating is fine boiler showing h9,H4 and now only showing HA, i hae read that it could be heat exchange overheat,dry fire thermister, could i repair it myself any advice greatly appreciated. :( :( :(