What Temperature Should I Set My Air Conditioner in Winter?
When the temperature drops, your air conditioner can be one of the easiest ways to keep your home warm and comfortable. If you have a reverse cycle air conditioner, it can provide both cooling in summer and heating in winter.
One of the most common questions homeowners ask is: what temperature should I set my air conditioner to in winter?
As a general guide, setting your air conditioner between 18°C and 20°C is a sensible starting point for winter heating. This range can help keep your home comfortable without placing unnecessary pressure on your system or increasing running costs more than needed.
The best setting will still depend on your home, insulation, room size, system type and personal comfort.
What Is the Best Air Conditioner Temperature for Winter?
For most homes, 18°C to 20°C is a good temperature range for winter.
This setting is usually warm enough to take the chill out of the room while keeping energy use under control. If you set the temperature much higher, the system may need to work harder for longer, which can increase running costs.
If your home still feels cold at 18°C to 20°C, there may be other factors affecting comfort, such as draughts, poor insulation, dirty filters or an air conditioning system that is not performing as efficiently as it should.
Does Setting the Temperature Higher Heat the Room Faster?
In most cases, no.
Setting your air conditioner to a much higher temperature does not usually heat the room faster. Instead, it may cause the system to run for longer as it tries to reach the higher setting.
For example, setting the system to 26°C will not necessarily warm the room faster than setting it to 20°C. It simply gives the system a higher target to reach.
A better approach is to set the temperature to a comfortable level and allow the system time to warm the room properly.
Why 18°C to 20°C Is a Good Starting Point
A winter setting between 18°C and 20°C can help balance comfort and efficiency.
This range can be suitable because it:
- keeps the room warm without overheating it
- helps reduce unnecessary energy use
- places less strain on the system
- supports more consistent comfort
- may help keep running costs more manageable
Some people may prefer the room slightly warmer, especially in living areas or homes with poor insulation. However, each degree higher can make the system work harder, particularly during cold weather.
How to Stay Warm Without Increasing Running Costs
Your temperature setting is important, but it is not the only factor that affects comfort and running costs.
To help your air conditioner work more efficiently in winter, you can:
- close windows and doors while the system is running
- seal obvious draughts around doors and windows
- use curtains or blinds to help retain warmth
- clean or replace filters regularly
- avoid setting the temperature much higher than needed
- use zoning if your system has it
- keep vents and indoor units clear from furniture or obstructions
- book regular air conditioning maintenance
If you are comparing the cost of different air conditioning options, you may also find our guide to split system vs ducted running costs helpful.
You can also read more about whether running your air conditioning unit in winter costs more.
Check the Mode Before Adjusting the Temperature
Before increasing the temperature, make sure the system is set to the correct mode.
For winter heating, your air conditioner should usually be set to heat mode, not cool, dry or fan-only mode.
If the system is set to the wrong mode, it may not warm the room properly, even if the temperature has been adjusted.
It is also worth checking the fan setting. In some cases, auto fan mode can help the system manage airflow more efficiently, while a higher fan setting may help circulate warm air more quickly through the room.
Why Your Air Conditioner May Not Be Heating Properly
If your air conditioner is set between 18°C and 20°C but the room still feels cold, the issue may not be the temperature setting.
Common reasons an air conditioner may struggle to heat include:
- dirty or blocked filters
- poor airflow
- blocked vents or indoor units
- an outdoor unit that needs cleaning
- low refrigerant levels
- poor insulation
- draughts in the home
- an older or undersized system
- a system that has not been serviced recently
If the system is not heating as well as it used to, it may be time to book an air conditioning service or maintenance check.
Split Systems and Winter Heating
Reverse cycle split systems are commonly used for winter heating because they can heat and cool a specific room or area.
They can be a practical option for bedrooms, home offices, apartments and living areas where whole-home ducted air conditioning is not required.
The key is choosing a system that is correctly sized for the room. A unit that is too small may struggle to heat the space, while a unit that is too large may not run efficiently.
If you are considering a new split system, you can read our guide to choosing the best split system air conditioner.
Ducted Air Conditioning in Winter
Ducted air conditioning can also be used for winter heating, especially when you want to warm multiple rooms or the whole home.
If your ducted system has zoning, you may be able to heat selected areas rather than running the whole system at once. This can help improve comfort and reduce unnecessary energy use.
For homes where several rooms need heating, ducted air conditioning may offer better coverage and a cleaner finish than multiple wall-mounted units.
You can learn more about the advantages of ducted air conditioning and what to consider when choosing the best ducted air conditioner.
When to Book an Air Conditioning Service
If your air conditioner is not heating properly, changing the temperature setting may not solve the issue.
It may be worth booking a service if:
- the system is blowing cool or lukewarm air
- the airflow feels weak
- some rooms are not heating evenly
- the system is making unusual noises
- there are unusual smells when the system runs
- energy bills have increased unexpectedly
- the unit keeps turning on and off
- the system has not been serviced recently
Regular servicing can help improve performance, identify issues early and support the long-term efficiency of the system.
Need Help With Winter Air Conditioning?
For homes across Manly, the Northern Beaches and greater Sydney, PSB Air can help with air conditioning maintenance, servicing and advice if your system is not heating as effectively as it should this winter.
Whether you have a split system, ducted system or reverse cycle air conditioner, our team can help review your system and recommend the next step.
Contact PSB Air to book an air conditioning service or discuss your winter heating needs.
