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How To Troubleshoot Common Home Air Conditioner Issues

Air conditioners are great for staying comfortable in those hot summer months. Plus, a heat pump air conditioner can even keep you toasty throughout winter. However, sometimes things can go wrong. But don’t worry; we’ve gathered our air con experts and compiled this guide on troubleshooting so you can fix any problems that may occur.

How To Troubleshoot Common Home Air Conditioner Issues

How do you diagnose an air conditioner problem?

Diagnosing an air conditioner problem involves a systematic process of identifying symptoms, performing visual inspections, and conducting tests. Here's a general guide on how to diagnose common air conditioner issues:

  • Your first port of call is the user manual’s troubleshooting section to see if your issue is listed.
  • Inspect the unit for any damage. Ensure the filter and fan vents are clean, whether it’s vented correctly and that there are no tight bends in the hose that prevent hot air from escaping.
  • Look at the power lead; is it plugged in correctly (not via an extension) and switched on? Make sure the lead doesn’t have any damage. Try a different socket.
  • If you’re using a remote and your unit isn’t switching on, try new batteries.
  • Ensure windows and doors are closed, as warm air flowing into the room makes the unit work harder to cool the room down.

If the above doesn’t answer your question, read on to find out more about common air conditioner problems and solutions.

How to install portable Air Conditioner

What are the common issue across the types of air conditioning units

Below are a few of the most common issues with air conditioners and ways to fix them. If you’re unsure or need any more help, give us a call on 03300 412 271 to speak to our friendly experts.

Why is my air conditioner not cooling?

If your unit isn’t cooling the room efficiently, there are a couple of things to consider.

First, the room. Is it too big for the unit to cool? How many devices or appliances are there? How many people are in the room? Check the BTUs required with our Coolculator. It’s also important to note that conservatories and rooms with lots of windows require double the stated BTU.

It could also be the venting. If hot air can’t escape, your air conditioner won’t cool the room effectively. Ensure the vent hose is as straight and as flat as possible, with no bends greater than 30 degrees. To check the unit is functioning properly, remove the hose from the unit and feel that the air coming out of the front is cold and the air coming out of the back is hot (when in cooling mode).

Did you know? BTU stands for British Thermal Unit, which is the amount of energy it takes to heat one pound of water (about a pint) by 1°F.

Why is water leaking from the air con unit?

The air pulled into the unit contains a lot of moisture, and any airflow problems may cause water to collect inside and then leak.

If it’s leaking from the exhaust hose, it’s probably been vented incorrectly. There’ll be condensation build-up in the hose, and the hot air can’t escape. Make sure the hose has no more than a 30-degree angle bend.

If it’s leaking from the base, check for visible cracks in the bottom. If you can’t see any damage, ensure the unit is on a level surface; otherwise, the drip tray (tank) may overflow and leak.

Why is my air conditioner very loud?

Some noise is normal (we list the dB noise level on our air conditioners so you know what to expect). If it’s louder than anticipated, try placing the unit on carpet, a small mat or a towel to help absorb any vibrations. If this doesn’t work, get in touch and we’ll help.

Air conditioners can become noisy due to extra strain on the fan. If you catch it early, it may not cause long-term damage, and correcting the venting may fix the problem. If the noise persists when the vent pipe isn’t connected, it means the fan is damaged.

Why does my air conditioner keep turning off?

Check your temperature setting. Once the room reaches the target temperature, the air conditioner automatically switches off to conserve energy. If the temperature in the room increases by 2-3 degrees, the air conditioner automatically switches back on to begin to cool the room again until the target temperature is met again.

Test the room’s ambient temperature and refer to your manual to check the ambient operating range of your air conditioner. It may malfunction if placed in a room that’s too hot or cold.

If the vent hose has more than a 30-degree angle bend, airflow can be restricted. This can result in reduced performance or damage to your air conditioner. If you struggle to straighten the hose, try placing the unit on a table.

Why does my air conditioner smell?

If your unit hasn’t been used for a while and it’s been stored away over winter, it may start to smell when you run it again in the summer. It’s a simple fix: make sure the water tank is empty and clean the filters by lightly running the brush extension of a vacuum cleaner over the filter. Once cleaned, the air con will clear the smell in the next 24 hours. You can even add essential oils to speed up the process.

Should I turn my air con unit off if it’s not cooling?

If your air con unit isn’t cooling the room, and you’ve tried the troubleshooting steps above, there’s probably a deeper issue. If it continues to run with a system malfunction, it could lead to further damage, so you should turn it off immediately.

How do you test an air conditioner compressor?

How do you test an air conditioner compressor?

This simple test will help you assess whether the compressor within the air conditioning unit is working correctly.

  • Remove the vent hose, place the air con unit in the centre of the room and switch it on.
  • Allow the unit to run for 20 minutes on the lowest setting.
  • At the end of the 20 minutes, you should feel hot air coming from the back and cold air from the front.
  • If this doesn’t work, give us a call on 03300 412 271 to speak to one of our air con experts.
Parting advice

Parting advice

We hope this comprehensive guide has helped you resolve your issue, but if you haven’t managed to, give us a call on 03300 412 271 to speak to our friendly team of air con experts.

If you’re in the market for a new air conditioner, check out our air con buying guide, which tells you everything you need to know. We can even install it for you; check out our air con installation page or give us a call on 0330 041 2742 for a free quote.

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