How can I fix my Ideal Classic HE15 condensing gas boiler?

When the programmer has instructed the boiler to turn off on the time sequence, the boiler still ignites for 1 minute every 10 minutes. However the pump does not come on but the boiler carrys on cycling.

The boiler is only 3 years old and is in a garage with a frost stat and a pipe stat. The only way to stop it cyling is to turn the programmer off at the mains.