I recently replaced the room thermostat for a new digital stat. thinking there was only 2 wires and a earth wire I couldn't go wrong! I was of the impression the stat switch was either open or closed?
When i conected the new stat, the was a bang from the boiler and the circuit breaker on the consumer unit tripped. Once reset, I noticed I had lost the electrical supply to the circuit board in the boiler. If i give the board a supply the boiler fires up but I suspect the pump is not powered as the boiler will overheat. A little knowledge can be dangerous !

Steve, September 2008

The pilot light is out the heating should have been on when I got in from work - but stone cold.
There is no 'obvious' ignition switch?

Karen, December 2010

by the sounds of it you have wiered the stat in wrong maybe reverse polarity, check wire on room stat make sure L and N wires are in correct place, to be honest your going to need a new pcb by the sounds of it, call a corgi engineer o and it maybe costly..

baximan, September 2008