How to clean your fan or heat pump

The last thing you want when you crank up the heat pump to cool you off or switch on a fan is to be breathing in any dust particles which have been laying on there since goodness knows when.

The Housekeeper cleaner Rachael Quin says heat pumps have become more mainstream over the past five years. but often we "fit and forget" to maintain them, as well as ceiling fans.

Aircon Heatpump Cleaners owner Kevin Bedford, who has been helping people keep their heat pumps in check for the past 16 years, says the less dust, the better your machine will operate.

"Once those filters get blocked up with dust, even a small amount of dust, it just blocks the air flow coming through the machine."

How often should I clean it?

It may depend on several factors, such as your unit's specifications and your usage, Quin says.

"The instructions in my booklet actually say if the unit hasn't been used regularly for a period of time, so let's say a few months, there's a function on there that you should [when you] first turn it on switch it to, and I think it gives it a bit of a clean out, not just the filters but everything, I think it does something to it."

Bedford suggests checking your heat pump unit regularly - every two to three weeks - when you vacuum, to give you an idea of the dust it collects so you'll know how often you actually need to be cleaning it.

If you keep your fan on overnight, it is probably collecting and moving more dust around, Quin says, so you will need to check on that once a month.

What do I need to clean my heat pump?

Cleaning residential heat pumps installed high on walls is relatively standard; often there's a latch to open the front cover of the indoor unit, where you'll find two filters to clean. For floor models, it may be one big filter.

Wash with either cool or warm water depending on what your unit manufacturer has recommended, Quin suggests.

"I make sure it's dried out completely [before putting the filter back in] and generally the filters are actually really, really fine. So in my unit, when I pull it out it doesn't really look like there's anything in there … But even if your filter looks clean, I think you should still rinse it under water."

Bedford recommends using a brush attachment on a vacuum cleaner if you're looking for a light clean. If you're washing it, you could use a light dishwashing liquid if it's very dirty, but don't use abrasive chemicals which can damage the filter.

"I use like a little wee shoe brush… soft bristle brush that's not gonna damage the filters."

For the outdoor unit, consider giving it a hose-down if it looks like it needs it, but also make sure nothing is obstructing it from sucking in air such as vegetation or cardboard boxes, Bedford says.

What about my fan? Are there any tricks for a ceiling one?

Quin recommends getting a telescopic duster tool that can bend over at a 90-degree angle - with these you can apply pressure to wipe without too much trouble.

Thinking of a dust repelling spray or wet cloth? Quin doesn't recommend it. She says a dry and thick chenille microfibre is all she uses but if there's still some sticky stuff left, she might go over it with a wet cloth or isopropyl alcohol diluted with water (30:70 ratio).

One trick TikTokers have been boasting about is to use an old pillowcase to drag across each blade. Quin says that's a good option when the fan is over the bed so it catches most of it without falling.

And similar to heat pump, you can use a brush attachment on a vacuum cleaner for a light clean - if your vacuum can reach that high or it's a small handheld one, Quin says.

Why is there mould growing in my heat pump?

Even though you clean filters, fine dust and airborne contaminants such as dust and pollen still get sucked through and cling to the coils and fan barrels, which can stop the unit from working properly or result in dripping, Bedford says.

That's where you want to get a professional to clean out the entire unit, including the drain pipe, using their special tools, he says.

"Over summertime … I get a lot of calls because people saying their heat pump is smelly or it's dripping, because it's blocked up with dirt and grime inside it.

"And mould spores can actually grow on the fan barrel. You'd be surprised how much build-up can come about just through the use of it."

Depending on your usage, he recommends getting a professional clean every 12 to 18 months. And of course if it's got wobbly legs or you feel like there's a bigger problem, like corrosion, you'll want to call a professional.

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