Fix Fault Halstead Hero 60

hero 60 will ignite & run with green light flash 5 seconds then remains on..locks out afet 5 mins, just replaced front isulation..do the fixing screws have to form a airtight seal?

hi my Halstead hero 60 when the time clock /thermostat call for heat the Boiler fires up, but when it cuts out on temperature it does not fire up again on demand , but the Fan runs. then I have to ... more

My Halstead Hero 60 Boiler keeps cutting in and out about every 15/20 seconds It is driving me mad Any advise please John