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  3. Common Air Conditioner Faults

Common Air Conditioner Faults

Is your aircon not working? Or is it blowing warm air? Air conditioners are more prone to breakdowns during summer and they are more likely to fail if they haven’t been serviced regularly. When your air conditioner stops functioning, it could be a small issue or a big one. Depending on the extent of the damage, it can be an easy fix or your unit might need to be replaced.

In this article, we will look at some of the most common faults associated with air conditioners and what you can do to repair your aircon them.

6 common problems with air conditioning systems

First and foremost, check if the unit is plugged in properly (if the unit is not hardwired). The plug can become dislodged or there could be an issue with the plug itself which could explain why your aircon isn’t working. If the unit is plugged in correctly, check the fuse and safety switch (if fitted) to ensure they have not tripped.

If there’s no electrical issue, there could be an issue with an internal component like:

  • Thermostat
  • Refrigerant
  • Frozen evaporator coils
  • Damaged fan
  • Dirty filters
  • Water leaks

Thermostat issues

If your room is too hot or too cold, it could be due to a faulty thermostat or sensor. A displaced sensor can prevent the unit from detecting the correct temperature and you could face erratic cooling cycles. Check if the sensor is placed correctly, it should be placed near the evaporator coil but shouldn't touch it. Adjust the sensor by carefully bending the wire that holds the sensor in place. If that doesn't fix the problem, call your local air conditioning technicians who can diagnose the exact reason for the problem.

Thermostat | Air Conditioning

Low refrigerant

If you can see ice building on the indoor unit or if you can hear a bubbling or hissing sound coming from the unit, it could be due to refrigerant leaks. Low levels of refrigerant or a leak can hinder the cooling process of the aircon. Refrigerant makes cooling possible and if there’s an issue, your room can remain hot/cold even if the aircon has been functioning for hours.

If the problem is due to a leak causing a low refrigerant level, it can be repaired and regassed to fix the problem. A licensed HVAC technician can test the gas levels, fix leaks, and regas the system with an appropriate level of refrigerant.

However, if there’s a bigger fault, then the whole unit may need to be replaced. Your air conditioner will perform better when the refrigerant level matches the manufacturer’s specifications.

Note: Refrigerant leaks are harmful to the environment and DIY regassing can be very dangerous, so call a professional immediately.

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Frozen Evaporator Coils

If the unit doesn’t receive enough air, the coil may freeze and prevent the refrigerant from absorbing heat from the indoor air. This would disrupt the flow of cool air in your room.

The evaporator coil will thaw if the unit is not being used. To correct this issue let the evaporator coil defrost for a day. You can speed up the process by running the unit on fan mode only as it will help melt away the ice without damaging the coil.

If this still doesn’t rectify the problem, you may need to call a licensed air conditioning technician.

Fan problems

A fan is fitted into the outdoor unit to allow the transfer of heat from indoors to outdoors (in the cool setting). If the fan fails to work, the compressor can overheat damaging the compressor.

Compressors can be quite expensive and the cost of replacement is often almost the same as buying a new unit. As this issue could be due to loose wiring or an electrical failure in the unit it can be difficult for you to diagnose the issue. So if the fan has stopped working, turn off the power supply to the aircon and call the professionals immediately.

Dirty or clogged filters

Dirty filters are one of the most common reasons for air conditioners to break down. If you forget to clean the filters, it can restrict the airflow and also cause the evaporator coil to freeze. This can cause the unit to fail prematurely.

The filters should be cleaned at least once a year. However, if you live in a dusty area or have pets, it might be better to clean them every 2-3 months. Most units have one filter that is easily accessible and can be cleaned by you, however, there are often filtration systems within the inside of the indoor unit which need to be cleaned by an aircon technician.

Dirty Air Conditioning Filters

Aircon water leaks

Water leaks from your aircon can be dangerous. Turn off the aircon and disconnect the electrical connection to the unit. A leaking aircon could be due to various reasons but it is best to call a professional who can resolve the problem quickly.

  • Inside your home - If water is leaking from the indoor unit, it could be due to a clogged drain line. If the drain line is clogged, the water can back up into your home and cause water damage. You can use a wet/dry vac to clear up the condensate line. Other possible reasons for water leaks could be a rusted drain pan, broken condensate pump, or dirty air filter.
  • Outside your home - some amount of water is normal but if you see a large amount of unexplained water around your outdoor unit, it could be due to a variety of reasons like improper installation, a dirty air filter, or a damaged condensate pan. Call your local aircon technician
Is your aircon leaking water | All Purpose Air Conditioning

Is it time to replace your aircon?

If your aircon keeps breaking down frequently and you have already spent a lot of money on repairs, perhaps it is time to replace the unit. Air conditioners usually last for 10 years but if the unit breaks down and has reached its expiry date, consider buying a new unit.

Air Conditioning Specialists | All Purpose Air Conditioning

3 easy ways to prevent aircon troubles

  • Replace the filters or clean reusable filters regularly
  • Clear the outdoor unit of leaves and debris
  • Ensure your aircon is serviced once or twice a year

The easiest way to prevent breakdowns is by carrying out preventative maintenance. If you need more tips or advice on air conditioner cleaning or servicing in Brisbane, feel free to give us a call at 1300 405 295 or fill out our online enquiry form.