How often should you clean heat pump filters?
The advice varies, so go with the one your manual matches. Samsung NZ says at least every 3 months, and more often with pets, dust or heavy use. Mitsubishi Electric NZ says at every change of season. BRANZ says several times a year if the heat pump gets frequent use.
Consumer NZ's reason is simple: clogged filters stop the unit running at its most efficient.
Cleaning the filters, step by step
Turn it off
Switch off at the remote, and at the isolating switch if your manual says to.
Reach it safely
Consumer NZ says high-wall filters can be hard to get at, particularly for older people and some people with disabilities, while a floor console's are a breeze. If you can't reach comfortably from a stable step, leave them for the service.
Slide them out and vacuum them
Lift the front panel the way the manual shows, and don't undo screws beyond that. Mitsubishi Electric NZ suggests a household vacuum with a small brush attachment. If your manual allows washing, let the filters dry completely before refitting.
Ducted? Find the return air filter
Ducted systems usually have their filter behind the return air grille, and Temperzone asks Hitachi owners to clean it regularly. If that means stretching off a ladder into the ceiling, leave it to a technician.
Keeping the outdoor unit clear
The outdoor unit needs room to breathe. BRANZ wants at least 500 mm clear on the faces where air goes in and out, and 100 mm on the others. Mitsubishi Electric NZ also warns against stacking furniture, pot plants or ornaments on it or close by, since anything blocking airflow cuts performance.
Its owner guide suggests clearing rubbish and plant matter every 6 months, then washing the unit and coil with car wash liquid (not dishwashing liquid) and hosing it down. Do it with the power off, keep the spray gentle, and don't take any panels off. Near the sea, Mitsubishi Electric NZ also makes looking after any applied corrosion protection the owner's job.
When does it need a technician's clean?
For a musty smell, Samsung NZ suggests airing the room and running Fan mode for 3 to 4 hours. Then clean the drain, wash the filters and run the self clean function if your unit has one. If the odour persists, it says the indoor unit may need a professional clean.
That means a technician taking the covers off and cleaning what you can't reach, including the coil and the drain tray. Ask for someone who does heat pump cleaning regularly, or the business that services your unit.
Skipping the basics can put the warranty at risk: Gree NZ's card excludes defects from an owner not checking and clearing filters, vents, coils and drainage pipes.
What you clean, and what a technician cleans
You can
- The filters, as often as your manual says.
- Leaves, weeds and clutter around the outdoor unit.
- Airing the room and running Fan mode for a stale smell.
Leave to a licensed installer
- Taking off covers and casings.
- Cleaning the indoor coil and drain tray.
- Clearing a blocked drain line.
- Anything near the wiring or the refrigerant pipes.
What we'd do
What we'd do between services
We'd set a phone reminder to vacuum the filters at each change of season, and more often through a winter of daily use. We'd tidy around the outdoor unit whenever we're doing the garden. And if a musty smell outlasted a filter clean and a few hours on Fan, we'd stop there and book a heat pump cleaning specialist rather than spraying anything into the unit.