Maintenance and servicing

One of the benefits of a heat pump is its reliability and low maintenance requirements compared to a gas boiler. However, regular checks are essential to ensure the system continues to operate at peak efficiency.

Owner maintenance tasks

You can perform several simple checks to keep your heat pump running smoothly.

1. Keep the outdoor unit clear

For air source heat pumps, the fan needs a steady flow of air.

  • Debris: Ensure no leaves, twigs, or litter are caught in the external fins.
  • Plants: Keep shrubs and plants trimmed back at least 1 metre from the unit.
  • Snow and ice: In winter, clear any significant snow buildup from the top and sides of the unit.

2. Check the system pressure

Most heat pumps have a pressure gauge (usually near the indoor cylinder).

  • Target pressure: Typically between 1.0 and 2.0 bar.
  • Action: If the pressure drops significantly, it may indicate a leak or that radiators need bleeding. Contact your installer if you are unsure how to top it up.

3. Monitor the controls

Check your controller for any warning icons or error codes. Most modern heat pumps can be connected to the internet, allowing you (and sometimes your installer) to monitor performance remotely.

Professional annual service

Just like a boiler, we recommend an annual service by an MCS-certified engineer. This is often a requirement to keep your warranty valid.

A professional service typically includes:

  • Cleaning the evaporator coil: Removing any dirt or film that blocks heat transfer.
  • Checking the refrigerant: Ensuring there are no leaks and the charge level is correct.
  • Testing electrical connections: Checking for any loose or corroded wiring.
  • Cleaning filters: Most systems have an internal “Y-strainer” or magnetic filter that collects debris from the heating pipes.
  • Antifreeze check: For ground source systems, the concentration of the thermal fluid must be checked to prevent freezing.

When to call an engineer

You should contact your installer if you notice:

  1. Strange noises: Rattling or grinding sounds from the outdoor unit.
  2. Icing up: If the unit is covered in thick ice that doesn’t melt during its “defrost cycle”.
  3. Low flow temperature: If the house feels cold even when the heat pump is running constantly.
  4. High bills: A sudden spike in electricity usage without a change in weather.

Tip: Many installers offer service plans that cover the annual check and provide priority support if something goes wrong.