THE BOILER IS 12 YEARS OLD,RECENTLY HAS HAD NEW PCB,FAN ASSEMBLY,PRESSURE SWITCH & SERVICE.NOW THE THING KEEPS IGNITING-FIRING UP FOR 10-15 SECONDS,THEN CUTTING OUT FOR 5 SECONDS,THEN REPEATING OVER AGAIN.IF I LEAVE IT RUNNING THE RADS & WATER HEAT UP BUT THE PUMP GETS VERY HOT.ANY ADVICE WOULD BE APPRECIATED.
