how can i fix?

Is Pump Working? if not Repair/Repalce
Using Digital Thermometer
What is Temperature of Flow & Return At Boiler, if flow temp above 80'C repalce Thermistor
if not and boiler trips at less than 95'C Repalce Overheat Stat,
Diferential temperature between Flow & Return should be around 10-15'C, this would indicate correct flow rate thro boiler

There could be other causes such as pcb, or excessive Burner gas Pressure

So Best to get an Engineer in
www.gassaferegister.co.uk will assist to find a local engineer

www.elanar.co.uk
August 2009