MY BOILER SOMETIMES COMES ON AT THE SET TIME AND SOMETIMES DOESN'T? THE SAME WITH THE HOT TAP IF THE CENTRAL HEATING IS OFF, IT SEEMS LIKE SOMETHING IS STICKING. I HAVE TO GO AND TAP THE LEFT HAND SIDE OF THE CASING THEN IT COMES ON, SOMETIMES STAYS ON FOR THE DESIRED TIME SOMETIMES GOES OUT. I HAVE REPLACED THE FLOW SWITCH THINKING IT WAS THAT STICKING OBVOIUSLY NOT. WHEN IT'S WORKING IT'S GREAT,PLEASE CAN YOU ADVISE.

NEIL TAYLOR, November 2009

mine dos the same bang on the side and it comes on also my fan is running 24 hrs a day 200/64 days ayear is this normal

george gilmartin, January 2010

it could be a dry joint on the PCB. take it out carefully, turning electric off first. check all solder joints on back, tell tale circle crack in solder. resolder where needed.

combi mark, December 2009