the pilot wont light by you just turning a switch on the wall what type of boiler do you have.you may have to manually relight the pilot.if its not electronic ignition.there is a knob on the main gas valve on the boiler that you have to push in and press in the piezo spark button repeatedly look through the sight glass window and repeat until you see the pilot flame.hold the gas valve knob in until the flame stays alight usually about 30 seconds.release the gas valve knob slowly and providing the thermocouple heats up the pilot should stay alight.if it goes out it may be the thermocouple wants changing or it could be the pilot jet needs cleaning.make sure that all the other controls are calling for heat,roomstat programmer etc.
mrknowitall
October 2008