Every Year. Why? Because unfortunately they are dirty smelly devices that burn oil. Its as simple as that. Every time your boiler fires up, fuel is burnt and a bi-product of that is carbon. Over time carbon deposits onto parts of the burner module and inside the combustion chamber, consequently reducing the efficiency of the boiler over time. Having your oil boiler serviced once a year ensures it is in tip top condition and running at peak performance, meaning you are getting the most for your money with the fuel you are burning.

Keeping on top of maintenance also means you are prolonging the life of your boiler. Allowing carbon sooty deposits to build up inside the combustion chamber will result in less heat being exchanged to the water (which is where you want it) and back into the boiler resulting in the long term damage to the baffles, burner and the boiler itself through over heating.