ravenheat boiler820/20 switches its self on & off by the electric timer?

Possibly a cheap timer.

Try something like an ACL Drayton TimeClock/Programmer with battery backup.

Timers are not the most "well-made" items in the world from any manufacturer; but the Lifestyle range is my preference for ease of use and reliability.



Also; it might be worth just checking your incoming mains Voltage to ensure it is a stable 230-245V... If you have a varying incoming voltage that is prone to spiking, you will eat time-clocks and there's not much you can do except fit a surge device.

GasAid.co.uk
December 2006