The simplest way to choose is to look for the Energy Star mark, Energywise, a division of the Government's Energy Efficiency and Conservation Authority (EECA) says. The mark is awarded only to the most efficient heat pumps on the market and could save you $150 a year on running costs compared with a model with no star.
All pumps have an energy-rating label which helps you compare the efficiency of similarly sized models. The more stars the more energy efficient the unit.
The red stars are for heating efficiency and the blue stars for cooling efficiency.
The cost
The systems don't come cheap. Heat pump experts Energy Efficient Solutions say the cheapest model designed to heat a small room might cost $1800 installed, while a unit designed to heat the main living quarters in a house can range from $2800 to $4000 installed.
A high-end ducted system which operates from a central hub and offers climate control to every room can cost from $5500 to $12,500.
Government funding
Government funding for insulation and clean heating is available for homeowners, including landlords, whose houses were built before 2000.
Those who live in areas with high levels of air-particle pollution can receive funding to help subsidise the costs of replacing inefficient wood-burning fires with efficient heating systems such as approved wood and pellet burners, heat pumps and gas heaters with flues.
Householders who have a community services card can receive $2000 of funding and those without can receive $1000 off the new system's cost.
Before installing a heat pump
Energywise says it's best to put in ceiling and underfloor insulation before the pump. That way you'll be able to buy a smaller pump and your home will be cheaper to heat.
Choosing a quality brand from a reputable supplier which offers at least a five-year warranty on parts and labour will be worthwhile in the long term.
Heat pumps should also be bought to suit the room size - if it's too small it will have to work harder and cost extra to run.
What to ask your installer
Using a professional heat pump installer can save you hundreds of dollars long-term and avoid any warranty headaches, Energywise advises.
Good design and installation are fundamental to a heat pump's effectiveness and efficiency. So installing it yourself is not recommended and may also void the manufacturer's warranty.
An experienced installer can size the unit correctly, give you advice about environmental considerations such as sea spray or sulphur from geothermal activity, and will also be able to select the best locations for the unit.
When looking for an installer, ask them about their qualifications and experience, whether they hold the appropriate licence to carry out the required electrical work, and whether they follow EECA's good practice guide.
A reputable installer should provide a warranty for the heat pump and its installation.
Precautions in colder climates
Energywise says that people who live in colder climates should check whether the pump is going to perform efficiently between 0C and 5C because some are more prone to icing up.
For newer pumps to be awarded an Energy Star mark they must meet a requirement designed to ensure a correctly sized pump will perform efficiently in this low temperature range.
Tips for using a heat pump efficiently
Heat only the space you're actually using and remember to shut
doors and curtains to keep the heat in.
Set the thermostat to a healthy temperature. Aim for a minimum of 18C while using a space (or 20C if you have children, elderly, or people who are unwell in the home) and 16C in bedrooms overnight.
Don't set the thermostat higher than you need it. Setting the thermostat to the maximum won't heat up your room any faster but it can make your heat pump run less efficiently.
Learn to use the timer. Don't leave your heat pump on all day if you're not there.
Clean the filter inside and outside regularly.
