Frequently Asked Questions : Air conditioners

Dirty or clogged filters reduce the airflow and as a result, air that bypasses the filter may carry dirt directly into the evaporator coil and cause damage.

Cleaning your air conditioner’s filters regularly improves the efficiency of your unit and reduces the power consumption by up to 15%.

Dirty filters are bad for your health, especially for people with asthma or allergies. They may cause itchy eyes, runny nose and sneezing.

We recommend at least every 6 months, depending on your system and how much it is used. If you keep pets like cats and dogs, have elderly family members or kids, it should be serviced regularly on a quarterly basis.

We suggest subscribing to an annual service/maintenance plan with a leading HVAC company like AIRCON 4 YOU that is fully licenced and certified and can give you advice based on the age, size, and usage of your system to keep it running efficiently and smoothly and save you money on potential repairs.

The average lifespan of a filter is 12-13 months. We recommend cleaning split system filters at least once a year depending on the usage.

In commercial places like hair salons, restaurants, child care centres, and aged care facilities, cleaning or even hydro cleaning the unit every 6 months saves the running costs, adds to the life of the system, and increases efficiency.

If you have a ducted system, the filters should be changed at least every 6 months. For elderly residents and households with kids and pets, it is healthy and important to clean the filters at least every 6 months.

A standard air conditioner temperature should be set between 24-26 degrees for cooling in the summer to ensure maximum energy efficiency from your unit.

If you set your air conditioning temperature to 25 in summer, you could save up to 20 percent on your energy bill depending on the temperature of the environment.

The ideal temperature for air conditioner in winter is 21-22 degrees.

During chilly winter nights, you may start the temperature at 26 degrees and high fan motor just to warm your place quickly but remember to turn the temperature down if you want to save money on your energy bill and run your unit more energy efficient in the long run.

Using a ceiling fan in slow mode together with air conditioning can circulate the warm air faster to all areas of your house.

There is no doubt that regular annual service and maintenance of your system can save you money on your energy bills and the cost of repairs in the long run. There are common things that tell when your air conditioning system needs attention and service.

  • Smell. Any bad smell or funny odour from the unit like dirty socks indicate there is mould, dead or trapped animals and geckos.
  • Unusual noises like clicking or banging noise may indicate there is some loose internal parts.
  • Leaking water from the indoor unit.
  • Error or fault codes on the remote and blinking indoor unit.

Water leaking could have many different reasons.

It could be due to low refrigerant or gas level blockage in the drains.

If drain is clogged with dust, mold, or dirt the water backs up into your home.

Most people rely on the professional and technical advice by air conditioning specialists when it comes to choosing a suitable system for their building.

However, knowing what questions to ask often helps to make a better decision. Make sure to ask the air conditioning technician or specialist the following questions:

  • What size air conditioner do I need?
  • Can I choose a bigger AC for a small room?
  • What type air conditioning is suitable for my place: ducted, split, or multi?
  • Are you fully licenced and certified?
  • Does my electrical supply have the capacity for this system?
  • Can you get Strata Approval, if needed?
  • How long is the warranty for and what does it cover?

One of the common reasons for poor AC performance is usually lack of maintenance. We have found that over 50% of our air conditioning service calls during a year in winter and summer is due to lack of regular service and maintenance.

Regular quarterly or every-6-months service prevents unexpected malfunctions, extends the lifespan of your air conditioner, adds to the efficiency of your unit, eliminates the need for a new system, and saves you money on your energy bills.

Cockroaches, termites, and geckos are big threats to your outdoor units. They snuggle into your unit and get trapped. The heat inside the outdoor unit kills them and overtime they will cause damage to the electronic board.


  • Get a glue trap from Bunnings (the one that pest control guys use) and stick them inside your unit. It is also a good idea to glue another one on the outdoor unit. However, remember, if your outdoor unit is in the sun, you need to double glue the trap as the heat would highly likely melt the glue and it may come off. Make sure to check your outdoor unit every 3 months especially if it is in the bush or in the backyard on the ground, and replace the glue traps.
  • Put a mothball inside your outdoor unit. Geckos hate the smell of it.
  • Spray Lanoline inside and outside of your outdoor unit. It keeps the geckos and cockroaches away.

To determine the size of air conditioner you need, simply multiply the width of the room by the length of the room.

Then after you calculated the size of area you want to install the unit, follow this sizing guide to determine the KW capacity of the air conditioner.

Please consult our sizing guide for split systems so you get a better idea of what capacity air conditioner best suits your needs based on the size of area, size of windows, height and insulation of ceiling.

In summer, avoid trapping any heat inside the house. Close the curtains, drapes, and shades. Adjust the temperature of your air conditioning to 22-25 degrees to save on energy bills. Use timer on the remote panel so that when the room temperature reaches the desired degree, the system automatically switches off and uses less energy.

In winter, adjust the temperature of your air conditioner to 22 degrees to ensure maximum efficiency. Turn the temperature high e.g 26 degrees for 10-15 minutes and use a ceiling fan to circulate the warm air around the house. Then turn the temperature down to 22 degrees.

If your air conditioning system is ducted, make sure the roof is insulated so in summer and winter your unit doesn’t have to work harder to cool down or heat up the room.
Make sure you service your air conditioner regularly and change or clean the filters to allow your unit to run more efficiently.

Make sure an isolating switch is installed next to your outdoor unit.

When you are not using your air conditioner during spring or autumn, switch off the isolating switch so the power surge doesn’t cause any damage to your system.

Make sure the isolating switch is turned off to avoid any damage to your outdoor unit compressor or electronic board due to a power surge. Make sure there is no shrubs or weeds growing around the outdoor unit. Preferably cover the outdoor unit so dusts, geckos, leaves, and dirt don’t pile in the unit.

It is actually a good time to catch up on maintenance and avoid long waits and higher costs of service in the summer. Run the AC in fan mode first before turning it on. Let it blow for a solid 10 minutes. This will help get any dust out of the system before you turn it on Cool.

The average reverse cycle air conditioner costs around $0.13-$0.36 per hour to run for heating purposes. A ducted whole-house reverse cycle air conditioning system costs the most, at $1.45-$2.12 per hour, but switching off the zone motors in the areas you don’t need could potentially save you money on your energy bill.

The cost of a space heater whether it’s fan, electric, radiant, or oil is between $15-$55, if you buy from Kmart or Target.

But consumption of heaters are commonly given in watts and is something between 1800-2200W and that is something to be wary of. The average cost of space heaters are between $0.53-$0.66 KW per hour. You are billed KW per hour! This means if you only use 1 fan heater or space heater for 3 hours a day, it will cost you about $143-178 for 90 days winter period on top of your normal energy bill.

Whereas a reverse cycle air conditioning costs around $0.13-$0.36 KW per hour, which means for 90 days in winter if you run your AC for 3 hours a day, it will cost you up to $100 on top of your normal energy bill. It is almost half!

You can use the NSW Government rebate for any new installation or replacement of energy efficient air conditioner with high star rating. You need to be a NSW resident, buy an energy efficient system, and use an approved installer in your area (like AIRCON 4 YOU) to purchase and install your air conditioner.

Make sure the discount subsidized by the NSW Government is included in the quote. Also you need to know that not all brands are eligible for rebate. You can check the list of eligible products on this website: