How often you need to clean the filter in your air-conditioner for maximum efficiency

When was the last time you cleaned the filters in your air-conditioning unit?

With electricity prices on the rise, it's a simple task that can save you money and keep you warm in winter.

Reverse-cycle air conditioners — also known as heat pumps in Tasmania — have a very fine filter.

"The filter is probably the one thing that you, as the owner of the heat pump, needs to take care of," says Andre Morrisby, the general manager of an air-conditioning business in Hobart, Tasmania.

"The more debris that builds up on [the filter], the less air gets through it and the more expensive your system is going to be to run."

"It's like trying to suck air through a piece of carpet," he tells ABC Radio Hobart's Leon Compton.

How often you need to clean the filter (and how to do it)

How often you need to clean the filters will depend on your home and who lives there.

"If you clean [the filters] regularly, every two to three weeks, depending on your home … it will increase the efficiency, it will make the machine run better and you will be warmer," Mr Morrisby says. 

If you run a tight ship, dust regularly and are generally neat and tidy, you might get away with cleaning it every "four weeks" Mr Morrisby says.

"If you've got five kids like me, you might want to do it a little bit more frequently." 

If you've never done this before, a heat pump has an outdoor and an indoor unit, and the filters are in the indoor unit.

Units may vary and it's best to consult the manual for your particular unit for instructions on removing the filters. 

Once the filter is extracted there are a few ways to clean them. 

"Or you can use some warm, soapy water and dry them in the sunlight," he says.

The boxy outdoor unit needs a lot less attention than the indoor unit it is connected to.

"Basically, all you want to do is make sure it's clear of debris," Mr Morrisby says.

He adds manufacturers recommend servicing units every 12 to 18 months. 

Should you leave it running overnight in winter?

When asked about switching the heater on in the morning, Mr Morrisby says "the most efficient way to run a heat pump is to leave it running overnight". 

The trick is to turn it down to a lower heat before you go to bed.

"Drop it down to 14, 15, 16 [degrees Celcius], what you prefer and what you can afford."

It means the unit isn't working hard to bring the temperature up from zero to 20 degrees, if you live in a place where temperatures plunge overnight. 

It is also not a good idea to turn it on and off multiple times a the day.

"Turning it on and off [is] a big consumption of power," he says.

"I don't say leave it running all winter, I say leave it running during those really cold weeks of winter."

This article contains general information only. You should consider obtaining independent professional advice in relation to your particular circumstances.