is it a promax? if so it's probably the timer or room thermostat that's faulty, particularly if it's a danfoss room thermstat as there is a known fault with them and a stack of promax boilers were fitted with them. turn on all the contols (timer on constant, room thermostat right up and boiler thermostat right up), if the heating demand light on the boiler does not light then there's a problem with the timer or room stat.
Ian, August 2010
