Firstly, it has NO pilot light!
IF? your external controls (clock AND roomstat) are calling for heat, it'll be either the temprature control (dial on the front) is set to minimum, or the synchron motor on the diverter valve isn't operating.
I would initially suspect the roomstat to be set on about 20c and the ambient temprature to be 20 or over.
Changed plenty of the motors, takes all of 5 minutes if established to be the case.
Carefree
August 2010