The short answer
- Heat pumps should be serviced once a year, as manufacturers such as Daikin recommend.
- Many manufacturers make an annual service a condition of their warranty, so keep a record of every visit.
- A typical service takes around an hour and covers refrigerant and pressure checks, electrical safety, filters, coils, flow rates and controls.
- Between services, keep the outdoor unit clear of leaves, debris and snow, and call us if it becomes noisy, underperforms or shows a fault code.
How often to service a heat pump
Once a year. Daikin recommends an annual service and describes it as an MOT for your heating system, and Vaillant's heat pump service plans are built around one visit a year. The same interval applies to air source and ground source heat pumps.
In February 2025 the Heat Pump Association published a list of recommended minimum annual service checks for air, ground and water source heat pumps. It's a baseline for engineers to use alongside the manufacturer's own instructions, which always come first.
What an annual service checks
Our heat pump service includes:
| Check | Why it matters |
|---|---|
| Full system performance testing | Confirms the heat pump is delivering the heat and efficiency it should |
| Refrigerant and pressure checks | Low refrigerant or system pressure cuts output and can cause faults |
| Electrical safety inspection | Finds loose, damaged or overheating connections |
| Filter and coil cleaning | Blocked filters and dirty coils restrict flow and airflow |
| Flow rate verification | Too little water flow lowers efficiency and can trigger fault codes |
| Controller optimisation | Settings that drift or don't suit your home waste energy |
Daikin says a typical service takes around an hour. We record what we've checked and anything we recommend, so you have a service history for the system.
Servicing and your warranty
Many manufacturers tie their warranty to annual servicing. Daikin states that annual servicing is a requirement to maintain the warranty, and Vaillant's Cover & Care packages include an annual service to maintain the guarantee, with the service date based on your installation date.
Warranty terms differ between manufacturers and products, so check the documents you were given at handover. If you can't find them, we can help work out what applies to your system at the first visit.
Refrigerant and F-gas checks
Heat pumps contain refrigerant in a sealed circuit. Under the F-gas rules, equipment containing 5 tonnes of CO₂ equivalent or more of fluorinated gas must be leak checked at least every 12 months. Hermetically sealed systems only need regular leak checks from 10 tonnes of CO₂ equivalent.
Many domestic heat pumps fall below these thresholds, and some use refrigerants that aren't F-gases at all, so a formal leak check isn't always a legal requirement. We still check refrigerant pressures at every service, because a slow leak reduces performance long before the heat pump stops.
What you can do between services
- Keep the area around the outdoor unit clear of leaves, debris and snow, so air can flow freely.
- Make sure furniture and curtains aren't blocking indoor units or vents.
- Keep your heating controls on a steady temperature and schedule rather than turning them up and down.
- Note any change in noise, performance or running costs, and any code shown on the controller.
If something isn't right, our guide to what to check when a heat pump stops working covers the safe checks you can make before calling us.
Signs it needs attention sooner
Don't wait for the annual service if your heat pump:
- is noisy or making a new noise
- is underperforming, or your rooms or hot water aren't getting as warm
- is showing a fault code
- keeps building up ice that doesn't clear
Our engineers provide fast fault diagnosis and repair. See heat pump servicing and repairs, emergency repairs, or put every system you own on one annual schedule with a PPM contract. Thinking about a new heat pump instead? Our installation team at Solwat Green Energy can help.
Common questions
How long does a heat pump service take?
Usually around an hour, according to Daikin. Larger systems, ground source heat pumps and systems with several units can take longer.
Can you service a heat pump that someone else installed?
Yes. We service air source and ground source heat pumps fitted by other installers as well as our own, and check the warranty position and paperwork at the first visit.
Do I need a service if my heat pump seems to be working fine?
Yes. Many problems, such as a slow refrigerant leak, a blocked strainer or drifting controls, reduce efficiency long before the heat pump stops. An annual service finds them early and, where your manufacturer requires it, helps keep your warranty valid.