How it suits a warm temperate city
The national building code puts Adelaide in climate zone 5, warm temperate, between Whyalla's zone 4 and Mount Gambier's zone 6. That middle position is why a system chosen only for summer can disappoint in winter, and the other way round.
Reverse cycle moves heat rather than making it. The ACT Government says it turns each unit of electricity into 3 to 6 units of heat, and that good systems keep working at -10 degrees, so a frosty Hills morning is well within what a good unit is built for.
Adelaide facts that shape the choice
The average zone
On the zoned energy rating label, Adelaide falls in the average climate zone. Compare the stars for that zone, blue for cooling and red for heating, between units of the same size.
Gas homes
Greater Adelaide is on Australian Gas Networks' system. If your gas heater is ageing and you'd like cooling too, reverse cycle is the replacement to weigh up first. Our reverse cycle or gas guide sets out the trade-offs.
Frosty Hills mornings
Frosts are common in the Adelaide Hills valleys. Mitsubishi Electric says a unit on heat in cold, damp weather can stop for up to 10 minutes to defrost the outdoor unit, and that's normal.
Heat that bites
Adelaide has topped 40 degrees on several days in a summer. ActronAir says cooling capacity falls above 35, so the cooling figure needs to suit your hottest rooms too.
Reverse cycle or a gas heater in Adelaide?
| Reverse cycle | Gas heater | |
|---|---|---|
| Heating | 3 to 6 units of heat per unit of power, the ACT Government says | Heats quickly |
| Cooling | Yes, the same system | No, you'd need separate cooling |
| Servicing | Mitsubishi Electric recommends yearly | At least every two years by a gasfitter, ESV says |
| Carbon monoxide | Doesn't burn fuel | Any gas heater can spill it, ESV warns |
| Running costs | Much lower, by the ACT Government's comparison | Higher, by the same comparison |
Running it sensibly
RAA in South Australia sets out the method for running costs: find the unit's input power in kW, multiply it by your electricity rate per kWh, then by the hours you run it. Use the input power, not the capacity on the box. Our running cost tool does those sums with your own tariff.
Settings matter as much as the unit. The federal Energy Rating calculator suggests 18 to 20 degrees for heating and 25 to 27 for cooling, and says each degree beyond that could add 10% to your electricity bill.
Questions to ask before you buy
- What's the heating capacity, and how many heating stars does it get in the average zone?
- Is the size based on a heat load for my rooms?
- If I'm replacing gas, who disconnects the old heater and makes the gas line safe?
- For ducted, will it need new ducts?
- How often do you install reverse cycle systems like this one?
What we'd do
If it were our home
If the gas heater were old and the house needed cooling anyway, we'd have reverse cycle quoted as the replacement rather than a new gas unit, and choose the model on its heating stars for the average zone. We'd ask for a heat load on the rooms and keep the winter setting around 18 to 20 degrees.
Tell us what you're replacing and your postcode. Licence-checked reverse cycle specialists near you can see the job, and we only release your contact details to the one who takes it. The national reverse cycle page explains how heat pumps work, and our Adelaide page covers the city as a whole.
