What Does a Boiler Service Include?

What an annual boiler service covers, how to prepare, and how servicing relates to warranties and landlord checks.

Last updated: 2026-09-01

An annual service is an inspection against the manufacturer’s schedule. It is not a repair. It keeps the boiler safe, efficient and within warranty terms.

Typical checks

The exact list follows the boiler’s manual, but broadly: visual condition and installation compliance, flue integrity and termination, ventilation, gas inlet and burner pressures, combustion performance with a flue gas analyser, seals and electrodes, condensate trap and pipework, expansion vessel charge where accessible, and operation of controls and safety devices.

How to prepare

Clear access to the boiler and airing cupboard, the manual or warranty details to hand, and a note of anything unusual such as noises, pressure loss or fault codes. A routine service on an accessible boiler typically takes under an hour.

Servicing, gas safety checks and repairs

Servicing maintains the appliance. A landlord gas safety check (CP12) documents safety across all gas appliances in a rental property. The two are related but separate pieces of paperwork. Repairs fix faults found during either, and are quoted separately. All three can be booked through our boiler servicing page.