How to use your heat pump efficiently this winter

Heat pump efficiency and settings for winter

Given that heating can account for over 35% of our winter power bill, choosing the best option to heat your home is important.

Over 25% of all New Zealand households now use a heat pump, making them New Zealand's third most popular heating solution.

When you want to get the most out of your heat pump, it's important to know that one size does not fit all. Choosing the right model for your space, using it correctly and regular maintenance could see you saving on those winter power bills for years to come.

Below we cover some things to look for if you're purchasing a new heat pump. And, if you already have one, we give you some handy tips for the best way to use a heat pump efficiently during winter.

Heat pump efficiency

Heat pumps are a very cost-effective alternative to traditional electric heating options because they move heat, rather than generate heat. They are the most energy efficient and cost-effective electric way to keep your home warm and dry during the cooler months.

Heat pump settings for winter in New Zealand

Using the right settings will help you use your heat pump more efficiently throughout the winter. Familiarise yourself with the remote for your unit, and in winter make sure you are using the Heat setting (indicated by a sun icon on many models). Adjusting the swing setting can also improve efficiency - if you direct the warm air down across the floor it will rise, warming the whole room.

Best temperature for heat pump in winter

During the colder months in New Zealand, it's recommended to set your heat pump to around 18-22 degrees. While this might seem low for making your home extra toasty in the winter, setting the unit to very high temperatures will consume much more energy and put unnecessary load on your heat pump.

If it's cold enough that you want to run the heating all night, reduce the temperature down to around 16-18 degrees, this will ensure you'll wake up cosy and your use of the heat pump will still be really cost efficient.

How do heat pumps work?

Heat pump's heat a home by extracting warmth from outside, transferring it into your home. When it's warm outside, it reverses directions and acts like an air conditioner, removing heat from your home.

Heat pumps are an efficient way to heat your room during winter. They usually take around 10-20 minutes to bring a room up to the desired temperature, and maintain it easily.

Split-system heat pump

The most popular and simple-to-install system in New Zealand is the single split system, designed to heat only one room, usually your living area. If you choose the right size, and placement, it'll warm your whole house. They're particularly good for open plan living areas.

Ducted multi-heat pump system

These have a vent in every room and are ducted through the ceiling. They're less intrusive, but they're expensive to install. The cost of a ducted heat pump is $15,000 or more for an average sized 150m² home.

• Excess warmth from your heater is distributed to rooms via a super efficient inline ducting fan
• Via a filtered eave inlet your home is ventilated with a small amount of drier air to offset the moisture build-up (from cooking, drying, clothes, showering etc)
• Free, filtered warm air is automatically harvested from your roof space to offset heater costs. (Note: Summer Mode disables this function)
• Rooms are warmed as air circulates around the house continuously, and persistent condensation is gone  

How much does a heat pump cost to run?

Heat pumps are the most efficient way to keep your home cosy and warm in cold weather, and using a heat pump can save you money compared to other forms of heating.

A heat pump's running costs depend on how long you use it and its energy output. According to genless.govt.nz, a heat pump used 6 hours per day for 6 months of the year with an energy output of 6kWh will cost around $400 per year to run.

How much power does a heat pump use?

Heat pump power usage is comparatively low - costing the lowest cents per unit (kwH) of heat release when compared with other methods of heating your home, such as electric heaters, gas heaters or wood burners.

Using a heat pump instead of an equivalent heating solution in your living space can save you around $500 a year. In some situations, oil or fan heaters can still have their places in your home, particularly for heating small spaces, such as a study or a bedroom for short periods of time.

How to save money using your heat pump

• The best way to use a heat pump is to keep the setting low (18ºC - 20ºC). Don't set your heat pump to the maximum – it won't heat the room any quicker, but it will use more energy. Programme it to turn on 15 minutes before you need it instead.*
• Clean both your indoor and outdoor heat pump filter regularly – at least once a year. It's simple and quick to do this yourself unless the placement of the outside unit is difficult to get to.
• Only heat the space you're using. Don't have heat pumps going in bedrooms or in rooms you're not using.
• Turn off your heat pump when it's not in use. It can run for as long as you need, but make sure you switch it off when you're not using it.
• Close doors and curtains to keep the heat in.
• If you can, get your house insulated. The better insulated your home, the better it will hold the heat and the more energy efficient the heat pump will be.
• Use the timer function to heat the space 15 minutes before you use it, or invest in a Smart WiFi controlled heat pump so you can control it remotely using an App on your Smart phone.

* The recommended temperature is 18ºC or 20ºC for children or the elderly, and 16ºC for bedrooms overnight.

How much does it cost to install a heat pump?

Installing a heat pump may seem like a big up-front cost, but considering the savings from having cost-efficient home heating in the long run, getting a heat pump is a smart investment into improving your home.

How much does a heat pump cost?

Heat pump units can cost anywhere around $1,500 - $3,500 excluding installation costs. If you opt to go for a cheaper model, factor in that it may not be as efficient as it's more expensive equivalents, and if it breaks down and requires reinstallation, that'll cost you even more.

Consumer NZ have a comprehensive buying guide to heat pumps available in New Zealand when you're ready to choose the right model for your home. 

Cost to install a heat pump

Heat pump installation cost can cost between $750 to $1350 for a single system. This can be up to half the cost of the unit again, but good installation is critical to energy efficiency.

Make sure your installer complies with the EECA good practice guide to heat pump installation. Don't be afraid to shop around, as the cost of heat pump installation can vary more than the cost of units themselves.

Tips for choosing a heat pump

Heat pumps may be an efficient way to use electricity to heat your home, but you do need to select the correct heat pump for your home.

Heat pump size is the primary thing you'll need to consider - as this will determine how efficient your heating is - but you'll also want to choose a reliable brand. Installing a heat pump in your home is an investment, so choose a reputable brand to make sure you install a unit that's going to go the distance.

What size heat pump do I need?

Having the correct sized unit for your space and level of insulation is important. Too small and the heat pump will use more energy trying to keep the space warm. Too large and it'll be less efficient as you'll have to keep switching the unit off to stop it from overheating.

There are plenty of factors like your location, room sizes, insulation level and the number of people living in your household that determine what size is best for you.

Look for the energy star rating

The Energy Star rating helps to demonstrate your heat pump's efficiency. The lowest energy efficient heat pumps available in New Zealand are 250% efficient (they give $2.50 heat for every $1 of electricity used). The most efficient models on the market are over 500% efficient.

ENERGY STAR® qualified heat pumps use less energy compared to non-qualified model, and a heat pump with 4 stars on the Energy Rating Label generates 55% less emissions than a similar heat pump with only 1 star.

How to choose the correct sized model

What sized heat pump you'll need is based on:

• Where you live – some heat pumps do not perform as well in the cold, so if you regularly get below -5ºC outside, you need to choose one that will perform well, or the unit will spend excess energy defrosting
• Climate – seaside or geothermal areas need protection against corrosion
• The house's level of insulation
• How many windows there are and whether you have single or double-glazing
• Ceiling height and room size

As a rough guide, in an insulated house you'll need a heat pump with 120 Watts per m2. In a less insulated house choose around 150 Watts per m2.

To find the most energy efficient model for your home try using a heat pump size calculator, get started by checking out this handy Efficient Appliance Calculator.

Additional heat pump features

Most heat pumps in New Zealand come with basic features such as timers, dehumidifying modes and variable fan speeds so you have more control over when and how your unit is running.

If you're after extra usability, there are some advanced features to keep an eye out for. WiFi connected units let you control the heat pump remotely from your phone, and if you are prone to allergies - heat pumps with ionisation help to remove particles from the air.

Where you position the heat pump is key

Get the outside unit placement right

The outside unit needs good airflow, as much winter sun and as little frost as possible. They need to be protected from elements that might cause corrosion, such as sea spray.

South facing walls are not ideal for the outside unit. Also avoid positioning it under decking or other areas where the air doesn't circulate freely.

The units can be noisy so take this into consideration when choosing where you put them.

The indoor placement

Heat pump units come in three types: high-wall, floor-mounted console or ceiling cassettes.

Floor-mounts are the best for quick heating, but you need to have the floor space and they can't be blocked by furniture.

High-walls are also a good option and newer models are getting less and less obvious on your wall.

A ceiling cassette, where the indoor unit is mounted into the ceiling, is an option if you lack wall or floor space.

Interested in energy efficiency?

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