could be thermostat not set high enough as relies on ambient temreture in the house hase the pilot light gone out if so the casing should slide of restart the boiler with the red button press in and hold down for 3-5 seconds,under the digital reader is a circute board like most mcs,boilers could be faulty another possability could be the plate or compreser in the boiler get a local engeneere out for piece of mind hope this helps
c.mathieson, December 2009