Heating and cooling

When it comes to home heating and cooling, one of the most important things you can do is choose the most appropriate system to suit your home. The good news is that there is a system to suit you, your home, and your budget.

To help you make the right decision we have outlined exactly what each heating and cooling system has to offer, their advantages and suitability.

You can also visit an ActewAGL Energy Shop to obtain advice on a heating system to best suit your needs.

Ducted reverse-cycle systems

Area: whole house
Application: an efficient form of heating and air conditioning  

A reverse-cycle system is one of the best ways to heat and cool your home with electricity. They use as little as 1/3 of the electricity to heat your home to the desired temperature, compared to standard electric heating.

A reverse-cycle airconditioner, or "heat pump", extracts heat from the outside air and transfers it into your home. This process is reversed in summer to cool your home. They are the most energy efficient electric system to run and will add value to your home.

Ducted systems

Ducted systems regulate temperatures throughout a house using a series of ducts in the floor or ceiling. The compressor unit is located outside the house. These systems can be zoned allowing heating and cooling only in those parts of the house that are occupied.

Wall split reverse-cycle systems

Area: single room, open plan design
Application: units should be used when heating/cooling one room, multi-split systems allow more than one room to be heated/cooled (twin heads). As with ducted reverse cycle systems, they are efficient.

A reverse cycle system is one of the best ways to heat and cool your home with electricity. They use as little as 1/3 of the electricity to heat your home to the desired temperature, compared to standard electric heating.

A reverse cycle airconditioner, or "heat pump", extracts heat from the outside air and transfers it into your home. This process is reversed in summer to cool your home. They are the most energy efficient electric system to run and will add value to your home.

Split systems

A split system separates the compressor, located outside the house, from the console section and fan inside the house. Insulated pipes and electric wiring connect these units. The console unit can be either wall-mounted or floor-mounted and suit a range of heating requirements, from single rooms to open-plan designs.

Electric in-slab heating

Area: all rooms
Application

  • zoned systems
  • should run continuously in winter
  • system heats using off-peak electricity providing sufficient heat for a 24-hour period
  • especially suitable for people suffering allergies or respiratory complaints
  • expected lifetime 40 years

In-slab heating warms the floor and slowly releases the heat throughout the day and night. The floor becomes the heat source, evenly distributing warmth throughout the house. In-slab heating must be installed during construction. Insulated cables are attached to the steel reinforcement of the slab before the concrete is poured.

Heating at off-peak tariffs saves money. The slab warms overnight and releases the stored heat throughout the day and night. The entire slab or zoned areas can be heated. Slab heating is clean, silent, distributes heat uniformly and incorporates thermostat controls.

The "dos and don’ts" of electric slab heating

Do:

  • switch the system on at the start of the heating season (typically May to October) and simply leave it to run
  • set the lowest comfortable thermostat temperature, and keep the system on this. Every degree the thermostat is turned up adds about 10% to your running costs
  • a zoned system will maintain appropriate temperatures in each zone
  • consider using slab heating to provide background heating, especially in areas such as bedrooms, where lower temperatures are satisfactory
  • supplementary heating may be required in bedrooms and similar areas during periods of very cold weather. To boost temperatures in living areas, use a high-efficiency space heater such as a reverse cycle system.

Do not:

  • switch the system on and off to deliver instant heat. It takes at least 1 day for the slab to heat up to deliver sufficient heat to a room. Slab heating is designed to provide constant warmth 24 hours a day
  • use in-slab heating in homes where occupants are only home for short or irregular periods. Instead, consider a system which provides instant heat when you need it.

Electric space heating (radiant and convection)

Area:

  • bedrooms
  • bathrooms
  • study
  • workshop areas

Application

  • suitable for rooms requiring heating for short periods of time
  • not cost-effective to operate for long periods of time as it uses peak-rate electricity

Radiant heaters

Radiant heaters, like the sun, heat people, objects and surfaces within the room, which in turn, heat the air. There are several types of radiant heaters:

  • portable models such as under desk heaters
  • fixed heaters for individual rooms, including bathroom units
  • ceiling heaters.

As direct radiant heat performs better at lower temperatures than conventional forced air heating, lower thermostat settings can be used.

Convection heaters

Convection, or space heaters, gradually heat the air in a room from the ground up. As the warm air rises it circulates throughout the room, evenly distributing heat. These heaters are quiet, have enclosed elements, built-in thermostats, and timers allowing you to heat your home as required. Convection heaters can be plugged directly into a power point or wired in as a permanent fixture.

There are two types convection heating:

  • natural convection heating which includes oil-filled column and panel heaters, towel rails, skirting-board models and under-carpet heating
  • forced convection heating, which uses a fan to draw air over the heating elements and recirculate that air around the room.

Evaporative cooling

Area:

  • ducted
  • portable

Application

  • uses air passing over water saturated pads to cool home
  • delivers economical cooling

Evaporative coolers use the natural relationship between relative humidity, water and air temperature. Air from outside is drawn through the unit across water saturated filter pads by a large fan. As air passes through the filter pads evaporation occurs, causing the air's temperature to decrease. Once the air is cooled it is forced into the room and then exhausted via an open door or window.

Evaporative systems have controls that will vary the airflow by changing the fan speed. On days of high humidity the cooling effect will be significantly lower.

Ducted systems

These types of systems are installed to cool larger areas or entire homes. The evaporative unit is installed on top of the roof. Air is moved through a network of insulated ducts to air outlets to each room in the building. These outlets, or registers, are large to allow the air to be freely discharged into each area. Because of the high air flow needed for evaporative cooling it is not possible to cool individual rooms. The cooler air then travels through the rooms to open doors or windows, where it is exhausted.

A central panel installed inside your home provides control over the system. Some units also have timers and comfort controls. Automatic adjustment of cooling and fan speeds provides the preselected comfort level.

Portable systems

Portable units are designed for much smaller areas such as bedrooms. They must be backed up to an open door or window to draw in outside air. Portable units are fitted with a water gauge and only have basic controls.