Boiler Maintenance Checklist: Keep Your Heating Running Smoothly

A simple DIY guide to avoiding breakdowns and staying warm year-round

Your boiler works hard to keep your home warm, especially through the long winters. A bit of regular maintenance goes a long way in preventing costly breakdowns, improving efficiency, and extending the life of your system.

While some tasks should only be handled by a Gas Safe registered engineer, there are plenty of simple checks you can do yourself to keep your boiler in top shape.

Use our seasonal boiler maintenance checklist to stay ahead of problems and make sure your heating system is ready when you need it most.

Boiler Maintenance Checklist

Check for Leaks or Drips

Look under and around your boiler for any signs of water – leaks can indicate internal faults or pressure issues.
What to do: If you spot a leak, switch off the boiler and call a professional right away.

Monitor Boiler Pressure

Most boilers operate best between 1.0 and 2.0 bar. Low pressure can affect heating, while high pressure could damage the system.
What to do: Check the pressure gauge. If it’s too low, you may be able to re-pressurise using the filling loop (check your boiler manual). If it’s too high, call for support.

Test the Thermostat

If your rooms feel colder or hotter than the thermostat setting, it may need re-calibration or replacing.
What to do: Try adjusting the temperature and see how the boiler responds. For smart thermostats, check the app for accuracy or connectivity issues.

Bleed Your Radiators

Trapped air in the system can stop radiators from heating properly. Bleeding removes this air, improving heat distribution.
What to do: Use a radiator key to release trapped air until water flows steadily. Have a cloth and bowl ready to catch any drips.

Ensure Vents and Flues Are Clear

Your boiler’s flue (usually a white pipe outside) must be clear of obstructions like leaves, snow, or debris to ensure safe operation.
What to do: Visually inspect the flue and ventilation points, especially after storms or during winter.

Book Your Annual Service

An annual boiler service by a qualified engineer is essential. It keeps your boiler efficient, identifies hidden issues, and is often required to maintain warranties.
What to do: Ideally, schedule a service before autumn, so you’re ready when colder weather hits.