many thanks mickyg. i'm reassured now 
. the thermostat was actually replaced last year in the annual boiler service/maintenance, even though in retrospect i think it was unnecessary. so hopefully that will last a good few years anyway. and fingers crossed on the gas valve.
. the thermostat was actually replaced last year in the annual boiler service/maintenance, even though in retrospect i think it was unnecessary. so hopefully that will last a good few years anyway. and fingers crossed on the gas valve.
