Heat pump servicing and maintenance: what it involves

What it actually means

A heat pump has fewer things to go wrong than a gas boiler in one respect: there is no combustion, no flue and no gas, so there is no annual gas safety check.

What it does have is a sealed refrigerant circuit, a water circuit through your radiators or underfloor pipes, a hot water cylinder, an electrical supply, a fan and a set of controls configured to a specific design. Servicing is mostly about the water side, the electrical side and the settings, rather than the refrigerant.

The refrigerant circuit in a domestic heat pump is normally factory-sealed and is not routinely topped up. If a system needs refrigerant, that indicates a leak, and the correct response is to find and repair it rather than simply recharge. Any work on the refrigerant circuit must be carried out by someone with the appropriate refrigerant handling qualification.

Why it matters for the outcome in your home

Performance drifts. Water quality degrades, filters and strainers collect debris, pressures fall slowly, and settings get changed. None of these announce themselves, and a system can lose efficiency gradually without ever showing a fault code.

Small problems become large ones. A partially blocked strainer restricts flow, which makes the heat pump work harder and can eventually trigger protection cutouts or damage components. Catching it at a service is straightforward; discovering it in January is not.

Warranties usually depend on it. Manufacturers commonly require documented annual servicing for the warranty to remain valid, and the requirement varies by product. This should be stated clearly in your handover documentation rather than buried.

Water quality protects the equipment. Correct inhibitor levels, filtration and, where relevant, glycol concentration all need checking rather than assuming.

What Airwarm checks and does about it

Airwarm’s aftercare starts before the first service is due.

1. Contact within 48 hours of commissioning

   A first check that the system is behaving as you expected.

2. Comfort review at two weeks

   This matters more than people expect, because it is when the compensation curve and schedules are refined against how the household lives.

3. Seasonal optimisation where required

   A setting that suits mild autumn weather is not automatically right in a cold snap.

4. An annual service reminder

   So the service that keeps the warranty valid does not quietly get missed.

The annual service scope covers system condition, filters, strainers, pressures, glycol where applicable, controls, weather compensation, temperatures, error history, hot water operation, emitters, noise and any concerns you have raised. Findings and recommendations are recorded and given to you, so you have a history rather than a receipt. Unvented cylinders have safety components that need periodic checking, and that is included where Airwarm installed or can properly assess the cylinder.

Airwarm also offers optimisation visits separately, remote support where practical, warranty coordination and fault diagnosis. A service confirms condition; an optimisation visit deliberately looks for a lower flow temperature or a better schedule.

What you can do between services

Not much needs doing, which is the point, but four things genuinely help.

• Keep the outdoor unit clear. It needs air flow, so leaves, snow drifts, shrubs, bins and garden furniture all matter. Do not enclose it in a decorative box that restricts air flow.
• Leave the settings alone unless you understand what you are changing. The most common cause of a heat pump underperforming after a year is that somebody adjusted something.
• Notice changes. A new noise, a room that has stopped reaching temperature, hot water that runs short, or the system running far more than it used to are all worth reporting.
• Check the pressure gauge occasionally, and report a falling reading rather than repeatedly topping it up. Repeated top-ups indicate a leak.

Common questions

“Heat pumps are maintenance free.” They need less attention than a boiler and no gas safety check, but treating them as maintenance free tends to cost efficiency quietly and warranty cover eventually.

“Servicing is just a way of selling a contract.” A service visit is how performance is protected and how the manufacturer’s warranty stays valid. Judge it by what the visit actually checks and what you are given afterwards.

“Any heating engineer can service a heat pump.” Many competent engineers can carry out the water-side and electrical checks. Refrigerant work requires specific qualification, and manufacturer-specific controls and fault diagnosis benefit from familiarity with that equipment.

“If it is heating the house, it is fine.” A system can heat the house perfectly while running hotter than designed, and that is invisible without looking at the settings and the data.

Next step

If you are considering a heat pump, factor long-term support into how you choose an installer, not just the installation. Clear advice, careful surveying, transparent design, respectful installation and long-term support.

If you already have a heat pump that has never been serviced, or it was installed by a business no longer supporting it, e-mail hello@airwarm.co.uk describing the make, model, age and what the system is doing. Airwarm will tell you honestly whether it is within scope.

If you are starting from scratch, begin with the Home Energy Assessment.