Choose an efficient reverse cycle heating and cooling system to suit your home and lifestyle, while saving energy costs and reducing emissions.
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Choosing a heating system is an important decision to make, as it locks in your heating costs for over a decade.
A system’s energy performance depends on the fuel available to you and how much space you need to heat. If you are replacing an existing heating system, you should consider if replacing like for like is the best option. New electric heat pump systems are more efficient and cheaper to run than gas ducted heating and rebates are available to assist with making the change.
For most Victorians, electric reverse cycle split systems are the most energy efficient, lowest cost heating option available that generates the lowest greenhouse emissions. If your house has a rooftop solar PV system, the benefits of heating with electric reverse cycle systems can be even greater.
Heating systems can generate heat with:
Choosing one depends on what fuel is available to you.
There are 2 types of heating systems:
If you need to heat your whole house, central heating would be more efficient. Ideally with a zoning capability, that allows you to heat only certain areas of your home.If you only want to heat a certain area, a room heater would be best.Generally, it’s cheaper to use a room heater. But it really depends on how big a space you’re heating. The larger the area, the larger the system you’ll need. The wrong sized system won’t heat your home efficiently and will cost you more money.If you can, get a supplier to visit and measure your home for a quote. If that’s not possible, provide them with a plan of your house, showing dimensions of the areas you want to heat. Also provide information about the insulation you use in your home.
This system has one outdoor unit that pulls heat from the outside air and transfers it to multiple indoor outlets (or heads) in different parts of the home through refrigeration piping.
Each indoor outlet can be controlled independently. Depending on how much space you want to heat, outlets can be operated:
Air temperature is controlled by a thermostat.
This system doesn’t generate heat directly using an electric element. Instead it uses heat pump technology to extract heat from the outside air. This makes it the most efficient form of electric heating.
Talk to your supplier or retailer about what size system would work best to heat your home. If you have a big home, you may need two systems to get good coverage.
From April 2020, new multi-split reverse-cycle air conditioners with a cooling capacity less than 30kW will be required to have a Zoned Energy Rating. The higher the rating the more efficient it is.
Ducted systems are required to have a Zoned Energy Rating but are not required to display it when sold. Ask the supplier or retailer about the rating.
We recommend you to set your temperature between 18°C to 20°C. Every 1°C higher will add around 10% to your heating bill.
Clean the filter of the indoor air handling units (heads) every month to ensure that the system operates effectively.
It’s important to have the air conditioner serviced regularly, as per the manufacturer’s instructions, to ensure it continues to operate efficiently.
Check how much multi-split reverse-cycle heating could cost to run.
This system provides whole house heating and cooling through one set of ducts, usually located in the roof space.
Heat from the outside air is pulled into a central unit. From there it’s blown through ductwork to outlets in the home. The air then returns to the indoor unit to be re-heated.
The indoor air temperature is controlled by a thermostat.
When buying a new system, you have the choice between two types of compressors:
There are some energy losses through the ductwork when the air conditioning is operating.
When having a new system installed, ask the installer about the R-value of the ductwork. This is the level of insulation. The better it is insulated, the lower these heat losses will be and the more efficient it will run.
From April 2020, new ducted reverse-cycle air conditioners with a cooling capacity less than 30kW will be required to have a Zoned Energy Rating. The higher the rating the more efficient the system is.
Ducted systems are required to have a Zoned Energy Rating but are not required to display it when sold. Ask the supplier or retailer about the rating.
The most efficient way to use your system is by zoning it. This allows you to split the house into different zones, so that you can limit it to only heat the areas you’re using.
Zoning your system depends on the design of your home and the placement of the return air grille. The better the zoning capability, the more control you’ll have over the energy consumption and running costs of the system.
It may also be possible to set different thermostat temperatures for different zones, providing you with an extra level of control.
Clean the filter of the return air grille every month to ensure that the system operates effectively.
Check how much ducted reverse-cycle heating could cost to run.
Gas ducted heating draws air from inside the home, heats it in a gas furnace and blows it through ducts to outlets located in different areas of your home.
A thermostat, usually located near the return air grille, is used to control the inside temperature.
If you have a builder, ask what energy (star) rating the gas ducted system is. It’s worth paying more for a high efficiency heater (5 stars or higher), as you’ll save more in the long run. Consider a system with zoning capability to save even more.
These systems lose energy through the ductwork. To minimise energy loss, ask the installer about the R-value of the ductwork. This is the level of insulation.
Aim for an R-value of 1.0 or higher. But be aware, the higher the R-value, the larger the diameter of the ductwork.
Gas ducted heaters have Gas Energy Rating labels to allow you to compare the energy efficiency of different heaters. The higher the rating the more efficient the heater is.
The most efficient temperature to set is between 18°C to 20°C. Every 1°C higher will add around 10% to your heating bill.
If you can, zone your system so that it only heats the areas you’re using.
Clean the filter of your return air grille monthly during the heating season to make sure the system operates effectively.
Have the gas furnace serviced at least every two years, to make sure it operates efficiently and safely.
Check how much gas ducted heating could cost to run.
Gas fired hydronic systems heat the whole house by heating water in a gas boiler and circulating it through one of the following:
The water then returns to the gas boiler to be re-heated.
The system is controlled by a thermostat monitoring the temperature of the room.
There are some energy losses from the pipework when the heating is operating.
When having a new hydronic heating system installed, ask the installer about the R-value of the cladding applied to the pipework. This is the level of insulation. The better it is insulated, the lower these heat losses will be and the more efficient it will run.
There are no energy rating labels for gas hydronic heating in Australia. Although the supplier should be able to provide information on the efficiency of the gas boiler.
New systems should have a boiler with an efficiency in the range of 75% to 85%. For higher efficiency consider a condensing boiler with an efficiency in the range of 89% to 94%. The higher the efficiency, the lower the running costs.
Gas boilers for hydronic heaters sold in Europe are required to have a European energy rating label. Suppliers of these products should be able to provide information on this rating. The rating is based on a G (lowest efficiency) to A (highest efficiency) scale:
These systems can be zoned. Radiators in individual rooms can be switched off by turning off the hot water supply, allowing you to limit the heating to just those areas where it’s needed. In some systems, there’s a thermostat in each room or zone, giving another level of control.
Have the gas boiler and pumping system serviced at least every two years, to make sure it operates efficiently and safely.
Check how much gas hydronic heating could cost to run.
Electric heating cables are laid in the concrete slab when the house is built. They heat the concrete to a low temperature which acts as a low temperature radiator, as well as heating the air in the room above.
Electricity is switched on to heat the slab for around 7 to 8 hours at night, using the cheaper off-peak electricity tariff. The slab then slowly releasing the heat into the house over the day.
This system may require an afternoon boost of electricity to heat the home comfortably during the evening.
This system is usually split into several heating zones. The operation of the heating in each zone is controlled by a thermostat.
Typically, the heating cables installed will have a power consumption of around 160 to 200 Watts per square metre of floor area heated. This can lead to a high electrical load when the heating is operating (for example 16 to 20kW for heating 100m2).
A concrete slab can store a large amount of heat. It can take several days to bring the house up to a comfortable temperature and will stay warm for several days once the heating is switched off. This means the system is not highly responsive, so if there are several warm days during the heating season, the house may be too warm, even if the heating system is turned off.
These systems are usually switched on at the start of the heating season and remain switched on until the end of the season, providing heating to large areas of the home all day, every day. They are best suited to cold climates, but are one of the most expensive heating systems to operate.
This system is laid in the concrete slab when building a house. You can only install this system in new builds.
Insulate the edge of the concrete slab to reduce heat losses.
Split the home into several zones that can be controlled separately to give you more control over the system’s energy consumption.
There are no Energy Rating Labels for in-slab electric heaters. All systems have essentially the same efficiency.
Set the thermostat to a lower temperature than you would normally use for systems that heat the air. Otherwise running costs can be significantly high. You should still be comfortable at these temperatures as they both radiate heat and heat the air.
Recommended temperatures are:
Consider lower temperatures for north facing windows, as they will be heated by the sun during the day.
Don’t lay carpet or timber flooring over in-slab heating, as it acts as insulation, reducing the heat transfer from the slab into the house.
Check how much electric in-slab heating could cost to run.
Room reverse-cycle air conditioners heat and cool a single room or open plan area. They come in:
Split systems have an outdoor unit that extracts the heat from the outside air and transfers it to an indoor unit with a heat exchanger and fan to blow the heated air around the room.
Most indoor units are wall mounted. Although floor and ceiling mounted units are also available.
Split systems are now one of the most common air conditioner types sold in Australia.
A window-wall mounted unit isn’t very common any more, but are still found in older houses. They’re less efficient and noisier than split systems.
These systems doesn’t generate heat directly using an electric element. Instead they use heat pump technology to extract heat from the outside air. This makes them the most efficient form of electric heating.
Room air conditioners are available in a wide range of output capacities. It’s important that the unit you choose is sized correctly for the room or area it’s heating.
When buying a new system either:
They will need to know:
Almost all room split systems sold now are ‘inverter’ models, which have a variable speed compressor. These are more efficient and generally quieter than the older compressors.
Window-wall units are less efficient and noisier than both standard and inverter split systems.
All room reverse-cycle air conditioners with wall mounted and floor mounted indoor units are required to have Energy Rating Labels. The higher the rating the more efficient the air conditioner is.
Split systems that have a ceiling mounted indoor unit and three-phase split systems are not required to have Energy Rating Labels, but are required to have energy ratings.
From April 2020, the Energy Rating Label used on room air conditioners is changing. So the air conditioners available in appliance retail stores can now carry either label.
The new Zoned Energy Rating Label shows the energy rating of the air conditioner based on its efficiency over a typical heating or cooling season, in three Australian climate zones:
Most of Victoria is covered by the cold zone, although the north-west corner of Victoria is covered by the average zone. The new labels will make it easier to identify the air conditioners that will perform best in the different climates.
The label also provides information on the measured noise level produced by the air conditioner in decibels (dB(A)). The outside noise level is important, as local councils are likely to place restrictions on noise levels in adjoining properties.
Read about Zoned Energy Rating labels.
Clean the filter of the indoor units of the split system or the window-wall unit every month to ensure that the system operates effectively.
Have the air conditioner serviced regularly, as per the manufacturer’s instructions, to ensure it continues to operate efficiently.
Check how much reverse-cycle air conditioning could cost to run.
Fixed electric heaters are usually fixed to a wall and are hard-wired to the switchboard.
This means they have a larger heating capacity than a portable electric heater, generally in the range of 3 to 4kW.
They are fan convection heaters that heat air and blow it around the room. They can heat medium to large sized rooms of up to 30 to 50 square metres.
They have higher running costs than other heating options.
Fixed electric heaters are no longer very common, but can be found in older houses and units.
There are no Energy Rating Labels for fixed electric heaters.
Close off the space that you’re heating to minimise the area. Block any draughts.
Consider having it replaced with an energy efficient room reverse-cycle air conditioner.
Check how much fixed electric heating could cost to run.
Portable electric heaters that plug into a power point come in a range of heating capacities. The maximum is 2.4kW.
They’re designed to heat a single room or small area of up to 20 to 30 square metres, for short periods.
While fairly cheap to buy, they are expensive to run for long periods.
Portable electric heaters include:
These types of heaters use an electric element to produce heat.
Fan convection heaters blow heated air around the room.
Oil-filled column heaters and panel heaters have hot surfaces that heat the air directly. They also produce some low-temperature radiant heat. As these heaters don’t have a fan to circulate air, they usually take longer to heat a room to a comfortable temperature. They don’t blow air around so they’re a better option for people who suffer from allergies.
These heaters are best suited to small living areas or bedrooms, where lower cost heating options are not available.
Choose one with a good quality electronic thermostat and digital temperature setting to lower running costs.
There are no Energy Rating Labels for portable electric heaters.
All portable electric heaters have essentially the same level of efficiency, but the effectiveness of the heating provided by different heaters can vary.
Portable electric heaters have built-in thermostats, but aren’t often very accuracy.
Check how much plug-in electric heating could cost to run.
Gas room heaters are often fixed and designed to heat a single room or open plan area by burning natural gas or LPG.
Gas heaters can be a low cost way of heating living areas, as long as the heater is:
There are two types:
If you have high ceilings consider one of the following:
Gas heaters can either be flued or unflued.
Flued gas heaters are permanently installed. The flue expels products from burning the gas to the outside. They can have an open flue or be ‘room sealed’ (also called balanced flued). Open flued heaters draw air from the room to burn the gas. Room sealed heaters draw air from outside to burn the gas.
If you have a new or well-sealed home, you should use a room sealed gas heater. Unflued and open flued gas heaters shouldn’t be used because they need adequate ventilation to operate safely.
Read Energy Safe Victoria’s safety alert for open flued gas heaters.
Unflued gas heaters produce a lot of water vapour which can cause condensation and mould.
In Victoria, installing new unflued gas heaters is banned. However if you have an existing unflued LPG heater, you can replace it with an unflued gas heater, as long as it meets these requirements:
You should consult a qualified gas fitter if you are replacing an existing unflued gas heater.
Gas room heaters have Gas Energy Rating labels to allow you to compare the energy efficiency of different heaters. The higher the rating the more efficient the heater is.
If you’re using natural gas for heating water and cooking, a natural gas heater can be a cost effective option for heating your home. You pay an annual supply charge of several hundred dollars a year for natural gas connection. This adds to the heating cost if you only use natural gas for heating.
Have your gas heater serviced by a qualified gas-fitter at least every two years, to ensure that it’s operating safely and efficiently. They should inspect the flue and test the carbon monoxide emissions.
Read about Energy Safe Victoria’s guide to heating your home with gas.
Check how much gas room heating could cost to run.
Slow combustion wood heaters burn wood in a metal firebox. Room air is drawn in at the base of the heater, and is heated when it passes around the back and sides of the firebox. Heated air is expelled from the top of the heater either by natural convection or with a convection fan.
They also generate radiated heat, both from the body of the heater and through the glass front of the heater.
Slow combustion heaters can produce a large amount of heat and can be used to heat large open plan areas.
The distribution of the heated air will be best if the heater has a fan. Reversible ceiling fans can be used to get a better distribution of heat in rooms with a high ceiling.
They can also be used with an ‘air shifter’ kit to heat larger areas of the home. The kit uses ductwork and an in-line fan to shift heated air into other parts of the home.
If you have access to a good quality, reasonably priced, supply of fire-wood and operate the heater properly, it can be one of the lowest cost options for heating large areas.
Slow combustion wood heaters are much more effective and efficient than an open fireplace.
However, smoke from wood heaters is a source of air pollution, and excess smoke can be a nuisance to neighbours and impact their health. You are required to ensure that wood smoke does not cause problems for your neighbours, and local councils have the power to enforce this. Read EPA’s information on air pollution caused by wood smoke and how to reduce it..
Buying the right sized heater is important. A model that is far too large for the area it is heating will have to be turned down which reduces efficiency, creates smoke and fouls the flue with creosote.
Ask the supplier or retailer about the rated heat output of the heater in kilowatts (kW). As a rule of thumb, the heater size should be around one-tenth of the floor area to be heated in square metres. So a 150 square metre area would require a heater with an output of around 15kW.
Look for models made to Australian Standard AS4013. These are designed to provide efficient heating with little pollution when used correctly. Heaters made to this standard will show the certification on their label.
Make sure the heater is installed according to Australian Standard AS2918.
You should check with your local council before having a slow combustion wood heater installed, as there may be restrictions in place.
There are no Energy Rating Labels for slow combustion wood heaters.
Use good quality, well cured, wood and operate the heater properly for it to operate efficiently and minimise the production of smoke.
If used incorrectly, slow combustion wood heaters can cause unnecessary air pollution.
Regularly maintain the system.
Have the flue of your heater cleaned regularly to prevent the build-up of creosote. It’s important to make sure the top of the flue remains free of obstructions for safe and efficient operation.
Check how much wood fire heating could cost to run.