To prevent premature failure of a heating system you should have you boiler serviced every 12 months. You can usually get this service from your energy provider or contact your local plumber. A service usually includes a boiler inspection and cleaning, fume testing and repairs if required.
If you have gas boiler make sure he/she is Gas Safe Registered or if you have an oil boiler, OFTEC registered.
WARNING: Not getting your boiler serviced could invalidate your home insurance.