Ducted Reverse Cycle Air Conditioning: How One System Heats and Cools Your Whole Home

Sydney homes swing from humid 40 degree days in January to chilly mornings in July, and most families end up juggling a split system in the lounge, a portable heater in the bedroom and a fan everywhere else. Ducted reverse cycle air conditioning replaces all of that with one quiet, hidden system that cools in summer, heats in winter and runs from a single controller or app.

At Paragon Air we have completed more than 3,500 installations since 2018, and ducted reverse cycle is the system we are asked about most by families in the Inner West, the Hills District, the Sutherland Shire and across Western Sydney. In this guide we explain how it works, how it compares to gas heating, what it costs and how to get the most out of it in winter.

What is ducted reverse cycle air conditioning?

Ducted reverse cycle air conditioning is a whole-home system that both heats and cools using the same equipment. It has three main parts:

• An indoor fan coil unit hidden in your roof cavity.
• An outdoor compressor unit that sits beside the house, much like a large split system.
• Insulated ductwork that carries conditioned air to discreet vents in the ceiling of each room.

You control everything from a wall controller or a smartphone app such as MyAir, AirTouch or iZone. Because the system is split into zones, you can heat or cool only the rooms you are using, rather than the whole house.

The big selling point is that one reverse cycle ducted air conditioning system does the job of two. You get ducted heating and cooling from a single installation, a single service and a single set of vents, with no wall-mounted heads or bulky heaters taking up space.

We install systems from Daikin, Actron Air and Mitsubishi Electric, with capacities ranging from about 5 kW for smaller homes up to 25 kW for large double storey homes. You can see the full range on our ducted air conditioning page.

How does reverse cycle heating work in winter?

A reverse cycle system does not burn fuel or heat an element to make warmth. Instead, it moves heat from one place to another using refrigerant, in the same way your fridge moves heat out of its cabinet.

• In summer, the system absorbs heat from inside your home and releases it outside through the outdoor unit.
• In winter, a reversing valve flips the cycle. The outdoor unit pulls heat energy from the outside air (yes, even on a cold Sydney morning) and the indoor unit releases it through your ducts.

Because it is moving heat rather than creating it, a good inverter system delivers several units of heat for every unit of electricity it uses. That is why reverse cycle is widely regarded as one of the most efficient ways to heat an Australian home.

A few things are normal in heating mode and worth knowing:

• The outdoor unit will occasionally run a short defrost cycle on very cold mornings. The indoor fan may pause for a few minutes while this happens.
• Warm air is released from ceiling vents, so it can take a little longer to feel warmth at floor level. Setting the fan to a lower speed helps the warm air settle.
• Sydney’s mild winters suit reverse cycle well. Outdoor temperatures rarely fall low enough to limit performance, even in colder pockets of Macarthur and the upper Hills District.

Is ducted reverse cycle cheaper to run than ducted gas heating?

For most Sydney homes, yes. Ducted gas heating burns gas to create heat, so it can never deliver more energy than the fuel it uses. A modern inverter reverse cycle system moves heat instead, which is why it typically uses far less energy to warm the same rooms.

There are other practical differences too:

If you already have rooftop solar, the case for reverse cycle gets even stronger, because daytime heating and cooling can be powered by your own panels. Removing gas heating can also mean you no longer need a gas connection at all, which saves the daily supply charge.

The exact running cost depends on your system size, insulation, zoning and electricity tariff. We break this down in more detail in our guide to how much ducted air conditioning costs to run.

Can you add air conditioning to an existing ducted heating system?

Sometimes, but it is rarely as simple as bolting a cooling unit onto your old gas heater. Whether it works depends on three things:

1. Duct size and condition. Cooling needs more airflow than heating, so older heating ducts are often too small. Many older ducts are also poorly insulated, which causes condensation and energy loss when cold air runs through them.
2. Vent locations. Gas heating often uses floor vents, while cooling works best from ceiling vents because cool air falls.
3. The age of your heater. If your gas unit is more than a decade old, adding a cooling coil to it usually makes less sense than replacing the lot.

In most Sydney homes we inspect, the better long-term option is to replace the gas heater with a single ducted reverse cycle aircon system. You end up with one modern unit that handles both jobs, properly sized ductwork and full zoning control.

Where existing ductwork is in good condition and correctly sized, we can sometimes reuse parts of it to keep costs down. The only way to know is an on-site inspection of your roof space, which we provide free of charge.

Is ducted refrigerated air conditioning the same as reverse cycle?

Mostly, yes. “Refrigerated” describes how the system cools: it uses refrigerant and a compressor, as opposed to an evaporative cooler that uses water. Almost every ducted refrigerated air conditioning system sold in Australia today is also reverse cycle, meaning it can heat as well.

The term you really want to compare against is ducted evaporative cooling:

• Ducted refrigerated (reverse cycle) cools and heats, dehumidifies the air, and works with windows closed. It handles Sydney’s humid summer days well.
• Ducted evaporative only cools, adds moisture to the air, and needs windows or doors open to work. It struggles on humid days, which are common across coastal Sydney.

For most homes from the Northern Beaches to St George, refrigerated reverse cycle is the better fit for year-round comfort. If a quote says “refrigerated” but does not mention heating, ask whether the unit is cooling only, as a small number of models are.

How much does ducted reverse cycle air conditioning cost in Sydney?

As an indicative guide, ducted reverse cycle air conditioning in Sydney typically costs:

Sources: Sydney figures from What’s The Damage (October 2026); national reverse cycle ducted installs typically fall between $12,000 and $17,000 according to SolarQuotes (January 2026).

The ducted reverse cycle air conditioning cost for your home will depend on:

• System size (kW), which is driven by floor area, ceiling height, insulation and window orientation.
• Number of zones and the controller you choose (MyAir, AirTouch or iZone).
• Brand and model, such as Daikin, Actron Air or Mitsubishi Electric.
• Roof access and storeys. Double storey homes sit at the top of the range.
• Removal of old equipment, such as an existing gas heater or worn ductwork.
• Electrical work, including any switchboard upgrades.

Every Paragon Air installation comes with a 5-year labour warranty on our workmanship, on top of the manufacturer warranty. Eligible NSW homeowners can also spread the cost with 0% interest finance up to $15,000 through Brighte, with up to 10 years to repay (subject to approval).

How do I use ducted air conditioning efficiently in winter?

A well-sized system with good habits can keep winter bills surprisingly low. These are the tips we give every customer:

1. Set a sensible temperature. Around 18 to 21 degrees is comfortable for most people. Every extra degree makes the system work harder for little gain in comfort.
2. Heat only the zones you use. Close the bedroom zones during the day and the living zones at night. Smart controllers like MyAir and AirTouch make this a tap on your phone.
3. Use timers and scheduling. Start the system 20 to 30 minutes before you wake up or get home, instead of leaving it running all day.
4. Keep the heat in. Close curtains and blinds at dusk, shut doors to unused rooms and seal obvious draughts.
5. Leave the fan on auto or low. This lets warm air settle into the room instead of being pushed around at high speed.
6. Clean your filters. Clean or replace return air filters every 6 to 12 months. A clogged filter restricts airflow and raises running costs.
7. Book an annual service. Most homes need a professional service once a year, ideally before winter or summer. Homes with heavy use or close to the coast benefit from twice a year.

Keep the area around the outdoor unit clear of plants, bins and stored items, so it can draw in air freely, especially during heating mode.

Get ducted reverse cycle air conditioning in Sydney with Paragon Air

If you are ready to swap the patchwork of heaters and split systems for one quiet, efficient system, we can help. Paragon Air is a family-owned Sydney business with a licensed and insured team of more than 15 technicians, and we install ducted reverse cycle air conditioning across Sydney, from the Eastern Suburbs and North Shore to Canterbury-Bankstown and Macarthur.

Here is what you get when you book with us:

• A free site inspection and a free, no-obligation quote.
• A system designed and sized for your home, not a one-size-fits-all package.
• Authorised dealers for Daikin, Actron Air and Mitsubishi Electric.
• Most ducted installations completed in 1 to 2 days.
• A 5-year labour warranty on all our workmanship.
• 0% interest finance options for eligible NSW homeowners.

Call us on 1300 507 892 or book your free site inspection online and enjoy year-round comfort from one system.

Frequently Asked Questions

How long does it take to install ducted reverse cycle air conditioning?

Most ducted reverse cycle air conditioning installs take 1 to 2 days once the system has been designed and quoted. Larger or double storey homes can take longer. Before we start, we do a free site inspection to check roof space access, plan the duct runs and confirm where the indoor and outdoor units will sit.

Do you need 3 phase power for ducted reverse cycle air conditioning?

Not always. Many residential ducted reverse cycle systems run on standard single phase power, while larger high capacity units may need a three phase supply. It depends on the model, the kW size and your switchboard, so we check your electrical setup during the free site inspection before we quote.

Can you close doors with ducted air conditioning?

Yes, but the system works best when air can flow back to the return air grille. Closing doors on rooms with supply vents can build pressure and reduce airflow. A well designed system allows for this with door gaps, transfer grilles or zoning, so you can shut off unused rooms rather than relying on closed doors.

How many zones do I need for ducted heating and cooling?

The right number of zones depends on your floor plan and how your household uses the home. Many Sydney families separate living areas from bedrooms so they only heat or cool the rooms in use. Smart controllers such as MyAir, AirTouch and iZone let you switch each zone on or off from your phone.

Does ducted reverse cycle air conditioning add value to a home?

It can. Whole home ducted heating and cooling is a feature many Sydney buyers look for, and discreet ceiling vents keep rooms clean and uncluttered. The exact value added varies by suburb and property type, so ask a local agent, but a well maintained, correctly sized system is a strong selling point.

How often should ducted reverse cycle air conditioning be serviced?

Once a year suits most homes, ideally before summer or winter. If your system runs hard or you live near the coast, twice a year is better. Between services, clean or replace the return air filter every 6 to 12 months to keep airflow strong and running costs down.