Forget internal fuse, check your power supply, you should have a fuse at fuse box, or a breaker and a fused spur unit next to the boiler. Ckeck them before anything, make sure that you have power getting to the unit, use atest meter or a neon screw driver do not forget the switch does that work, you are just,ping the gun going straight for a board, but if it does end up that, check on ebay, get most on tjere
SD, January 2013