Posted on 17 11 2021

Are you taking care of your heat pump?

Like every electrical appliance in your house, your heat pump needs regular maintenance to keep it working efficiently and effectively. This mainly involves cleaning the indoor unit and keeping the area around the outdoor unit clear.

You can do these tasks yourself as long as you’re comfortable working on a stepladder if your indoor unit is high on the wall. If you also get a professional to service your heat pump every couple of years, it should give you trouble-free heating and cooling for a very long time.

Most heat pump manufacturers recommend cleaning the indoor unit at every change of season. If you’re using your heat pump a lot, it’s a good idea to check the filters monthly and clean them if needed.

You can find detailed cleaning instructions in the operating manual (check the manufacturer’s website or search the model number online), but the general method is the same for most models. 

Before cleaning your heat pump, switch it off to keep yourself safe. The main power isolation switch is usually on the outdoor unit. And never apply water to any of the inner workings of a heat pump. 

Indoor unit

The most regular maintenance job is cleaning the filters, which collect dust and dirt from the air passing through the indoor unit. 

In most models, you can simply lift the front cover and slide the filters out for cleaning. Either use the upholstery brush on your vacuum cleaner or rinse the filter with water (no hotter than 50°C). Don’t use solvents or other harsh cleaners. Dry with a soft cloth or place in the shade to dry. 

While you’re dealing with the filters, check the cylindrical fan vanes and the heating/cooling fins for dirt build-up. Use your vacuum cleaner’s upholstery brush to gently vacuum dirt from the vanes and fins. Finally, clean the front panel with a damp cloth and mild detergent. 

Outdoor unit

Clean the outdoor unit whenever it looks dirty, but at least once or twice a year, and ensure that any water can drain away. Remove any clutter that could be sucked in by the fan. There should always be plenty of clear space for air to enter from the back and exit from the front of the unit.

Clear away any cobwebs, weeds or debris that could reduce airflow. Check the fan blades, fins and outer casing for any sign of rust and if you see any, deal with it as soon as possible. Clean the outdoor unit with a hose to remove any dirt or salt spray build-up; do this more often if you live near the sea.  


If your heat pump won’t switch on, check: 

  1. The batteries in the remote control 
  2. The fuse in your switchboard
  3. That the isolating switch on the outdoor unit is switched on
  4. If the heat pump still won’t go, call us on 0800 789 276.

If the heat pump won’t heat:

  1. Check that the heat mode is selected
  2. Turn the temperature up and run for 30 minutes
  3. Turn the fan speed up and run for 30 minutes 
  4. If the heat pump still won’t heat, call us on 0800 789 276.

If the power light is flashing: 

The heat pump is automatically defrosting, which can happen in very cold weather. Wait 30 minutes and it should start to heat again.


Even if you do the regular cleaning yourself, it’s worth having a professional check your heat pump every couple of years. The person who installed the unit is probably the best person to service it; they can measure the delivered air temperature and check the unit is operating properly.

Our experts at GreenSide are here to advise you about everything to do with heating and cooling your home. Get in touch with our team if you have any questions about maintaining or servicing your heat pump.


As an Owner-Occupier You May Be Eligible for a Warmer Kiwi Homes Subsidy