How often does a heat pump need a service?
The sources disagree, so here's who says what. Mitsubishi Electric NZ says standard home systems need servicing at least yearly, and that coastal, geothermal or commercial systems may need it more often. Rinnai NZ asks for maintenance every year from the install date by a Rinnai authorised service centre. Samsung NZ wants a technician it authorises to inspect the coils, refrigerant and gas levels once a year.
BRANZ sets a lower bar: regular filter cleaning by you, plus a service check every 2 to 3 years. Read your manual and your warranty terms, and while the warranty lasts, go with whichever is stricter.
Why your warranty cares about servicing
Several warranties spell it out. Gree NZ's warranty card says the warranty is void if regular maintenance isn't done at intervals of no more than 12 months by a qualified refrigeration and air conditioning tradesperson. Its repairer will ask to see the records. Samsung NZ's warranty doesn't cover damage from failing to maintain the product, and names the annual service and filter cleaning.
Temperzone says its Hitachi warranty doesn't apply where regular servicing hasn't been carried out. MHIAA, the distributor for Mitsubishi Heavy Industries, excludes faults caused by a lack of maintenance to drains, filters and heat exchangers. Tenancy Services' heating guide adds that straying from the maker's maintenance advice can also hurt performance, safety and even insurance cover.
So keep every service invoice with the purchase and install papers. Haier's warranty booklet asks owners to make all service and maintenance records available to the technician when they claim.
What a proper service should cover
Filters and the indoor coil
Filters out and cleaned, and the coil behind them checked for dust and grime. Mitsubishi Electric NZ says servicing clears salt, dust and contaminants from the coils and drain trays.
Drain tray and drain line
Cleared so condensation runs outside instead of down your wall. A blocked or kinked drain is the usual reason an indoor unit drips, according to Samsung NZ.
The outdoor coil and fins
Lint, dust and garden debris cleared off the fins so air moves freely. It's on the yearly maintenance list in Temperzone's warranty for Hitachi systems.
The refrigerant circuit
Checked, not routinely topped up. Refrigerant circulates in a sealed loop, so a low charge points to a leak that needs finding and fixing.
Corrosion and paintwork
Temperzone's yearly list includes touching up damaged paintwork to stop corrosion. Mitsubishi Electric NZ makes keeping up any applied corrosion protection part of the owner's responsibilities, which matters most near the sea.
Noise, controls and a written record
BRANZ says maintaining the outdoor unit stops worn bearings and other parts getting noisy. You should leave with a dated record of what was checked and anything that needs attention.
Who can service a heat pump?
Look for a heat pump servicing specialist, ideally one who works on your brand. Some brands are strict: Rinnai NZ's warranty excludes damage from service or repair work by anyone other than its accredited installers, service people or service centres.
Anyone opening the refrigerant circuit needs to be able to buy refrigerant. That comes from an industry arrangement, not a licensing law. Since the Commerce Commission authorised it in 2011, wholesalers have been able to sell only to holders of an RLTB Refrigerant Licence, or an EPA Approved Handler or Approved Filler test certificate.
Electrical work inside the unit is for a registered electrical worker. The EWRB says routine maintenance and appliance repairs don't need a Certificate of Compliance, so a normal service won't come with one, but any new fixed wiring will.
Warning signs when you book a service
- A phone call or door knock you didn't ask for, offering a service or a regas on the spot.
- A regas sold as routine. A well installed system shouldn't keep losing refrigerant.
- No written record of what was checked, cleaned or found.
- A business that can't tell you whether your brand's warranty accepts its servicing.
Between services, and on the day
You can
- Clean the filters as your manual says, and more often in a winter of daily use.
- Keep plants, leaves and clutter away from the outdoor unit.
- Note any drips, smells, noises or error codes to tell the technician.
- Keep every invoice and service record with the warranty papers.
Leave to a licensed installer
- Anything behind the covers of either unit.
- Cleaning the coils, drain tray and drain line.
- Checking the refrigerant circuit and repairing leaks.
- Electrical checks and repairs.
- Corrosion treatment and paint touch-ups.
What we'd do
How often we'd book one
While the warranty runs, we'd book a service at whatever interval the brand sets, which for many is yearly, and file every invoice. Once it's out of warranty, we'd stay yearly near the coast, in a geothermal area or for a unit that runs all winter. For a lightly used one inland, we'd stretch towards BRANZ's 2 to 3 years. The filters stay your job either way, and our heat pump cleaning page shows how.