Wood Heating

Output of heat is rated in kilowatts (kW). The amount of kilowatts you need will depend on where you are in Australia, the size of your home, how many windows there are, and if you have home insulation.  For example, an 180 square meter house that is well insulated will require a lower output than the same sized home with no insulation.   Heaters should be sized to accommodate average, rather than extreme, temperatures.

Ensure your choice of wood heater has been manufactured to all the rigorous Australian Standards applicable to wood heaters. All wood heaters manufactured since 1992 must adhere to AS/NZS 4013 – the Australian Standard for emissions ensuring they are clean burning and environmentally responsible.

Ensure your choice of wood heater has been manufactured to all the rigorous Australian Standards applicable to wood heaters. All wood heaters manufactured since 1992 must adhere to AS/NZS 4013 – the Australian Standard for emissions ensuring they are clean burning and environmentally responsible.

Ensure your choice of wood heater has been manufactured to all the rigorous Australian Standards applicable to wood heaters. All wood heaters manufactured since 1992 must adhere to AS/NZS 4013 – the Australian Standard for emissions ensuring they are clean burning and environmentally responsible.

Wood heaters provide heat in one or a combination of the following ways:

(A) Radiation (Radiant Heat)

(B) Convection

(C) Fan Forced Air Distribution

There are no clear performance differences between cast iron or plate steel construction, a painted or enamelled finish, however, there are important differences in heat delivery. The main ways are by direct radiation, convection or a combination of both.

Convection wood heaters have a ventilated casing around the firebox which is either tiled or fabricated from metal. Heat is distributed by convective currents, with cooler air being drawn in to rise between the firebox and the outer casing, keeping the outside of the unit relatively cool. Convection heaters transfer about two-thirds of their heat output by convection and about one third by radiation. Sometimes electric fans may be built in to increase the  convective air flow. Because warm air rises, these heaters tend to heat the room from the ceiling down, and as a result it takes longer for the warmth to be felt. Reversible ceiling fans can help overcome this. Convection wood heaters generally provide a fairly even heat throughout a room and because their exterior surfaces are lower in temperature than radiant models, they are less likely to cause burns from direct contact. A fireguard is still recommended.Convection wood heaters generally provide even heat throughout a room.

A fireplace insert is a wood heater specifically designed for installation within a masonry fireplace. Inserts are commonly used to convert open brick fireplaces, which are usually unable to produce sufficient heat. This type of conversion ensures that most of the heat is delivered to the room instead of being trapped in the masonry structure, or wasted via the chimney. Older installations allowed the emissions to exit directly into the chimney cavity. AS/NZS 2918 now requires a stainless steel flue be installed from the flue collar of the appliance to the top top the chimney greatly improving performance. The evolution of fireplace insert designs together with improved installation has enhanced performance to the extent that today’s fireplace inserts are almost as efficient as freestanding wood heater.

Another type of insert commonly known as a heat circulating fireplace can also be installed into an open masonry chimney and will provide a greatly improved performance and efficiency when compared to an open fireplace. They do not however, provide the same combustion efficiency as freestanding and fireplace inserts. This type of heater cannot provide an ‘overnight burn’ as it has an open (unsealed) front.