As the summer sets in, it’s time to repair and prepare the air conditioners to do its magic. Long forgotten for months, the air conditioner could cause some problems.

Almost 60 to 80% of Indian homes use air conditioning. However, some homeowners may run into trouble as soon as they start the appliance.

After a brief period of dormancy, the air conditioner could have several associated problems. It is imperative to give the unit a thorough checkup before using it.

Common AC Problems and Solutions

Like any other appliances, your air conditioner also needs regular tuning to deliver the best performance. If you do not maintain the machine, you would have to struggle the most when it is summer.

To ensure you do not lose your cool as the weather starts warming up, it would be right to identify some of the common problems you may face with the machine.

Common Air Conditioner Problems with Solutions

Here are a few common AC problems and the best possible solutions to fix them yourself without technician’s help.

1. The AC Does Not Turn On

It happens quite frequently.

When the AC does not turn out, you should check the thermostat batteries. The batteries, probably, are dead. Replace them.

However, if they are still in good condition, the thermostat could be causing a problem. Check is the cooling mode is on and the temperature settings are right.

If that also does not help, focus on the A/C circuit breaker. It may be ‘off’. Turn it ‘on’.

If none of these solutions works, you have to call your HVAC expert.

2. Water Leaking from Indoor AC Unit

If water is leaking from the indoor unit of the air conditioner, it needs maintenance.

When the condensate drain of the AC is clogged due to fungi or algae, it causes water to back up through the pipe and right into your room.

The condensate pump could be broken too. In that case, you have to replace it.

For either of these jobs, you should call a technician. If you want to DIY, read the manual carefully.

3. Water Leaking from Outdoor AC Unit

On a hot and humid day, you may see water puddle outside the house, right under the AC’s compressor.

There could be several reasons for this such as a broken condensate pan, dry air filter, improper installation, poor quality AC seal, etc.

Once the problem is diagnosed, turn off the air conditioner; disconnect the power supply. It is crucial to address this problem immediately. Call an expert.

Also See: How to Reduce AC Power Consumption Effectively?

4. The AC Air is not Cold Enough

If your house feels warm despite the air conditioner running, it is a sign of a problem.

  • When did you change the air filter? If you cannot remember, change it immediately.
  • Next, change the thermostat settings to the coldest temperature. If it does not work, you have to get a new one.
  • Inspect the air conditioner and its surrounding area to ensure there are no signs of vegetation or debris. Keep tall plants and bushes away.
  • Remove leaves that may have fallen on the AC unit. If you find any signs of refrigerant leaks affecting the A/C cooling, call an HVAC professional for a checkup.

An expert can repair and even replace the AC refrigerant reservoir. Examine the copper lines that enter into the condenser. One of the two copper lines is larger. When the refrigerant level is sufficient, the line sweats and it cold when touched.

If your home has old windows or insufficient insulation, it may heat your home relatively faster. You may use a blackout curtain at daytime or add insulation for better results.

If the ductwork leaks, the home could become warmer and humid when the AC is running.

An efficient HVAC technician performs the necessary tests to determine the actual cause.

5. The AC Does Not Cool Evenly

An air conditioner may run, but the temperature may fluctuate from time to time.

The leading cause of temperature fluctuations is a leakage in the ductwork, blocked registers or vents, or poor insulation. Make sure that all the vents throughout the house are open, unobstructed, and clean.

Homeowners often complain that south-facing rooms are usually hotter than the other part of the house.

If you are facing the same thing, use blackout curtains for the windows during the warmest daytime.

6. Noisy Air Conditioner

Squealing or screeching sounds coming from the blower motor is a sign of motor bearing problems or faulty belt. The belt might break. To prevent that, add lubricant to the oil port.

Rattling clanging, banging or thumping means there is some problem with the blower or motor assembly.

If you heard any such noise, turn off your unit immediately and call an HVAC expert.

If you hear a smacking sound when the blower is cold, it means something is sticking to the blower blades or near the blower. Turn it off and examine the blower for debris.

If the air conditioner makes a clicking sound when it is turned on and off, it indicates a relay problem.

If you hear a rattling sound when the fan turns on the compressor, it could be due to loose hardware or failing motor. Seek professional help.

7. AC Thermostat Issues

If the air conditioner’s thermostat is not working, or is not calibrated properly, the machine might not receive the signal to turn on.

If the thermostat is set to the lowest temperature but still the machine does not turn on, it indicates that you need professional help to re-calibrate or even replace the thermostat.

The calibration problem is very common in the older models of thermostats.

8. Drainage Difficulties

The air conditioner removes moisture from the room. The same collected moisture has to drain out.

Technically, the machine is designed to remove moisture from the space through a drainpipe into a filter and is then funneled into the drain.

However, if the drain clogs and the filter starts overflowing, the water would back up and damage the system. This backup could lead to water leaks, which may further damage the building.

Do not ignore the drainage lines when you are troubleshooting.

9. Dirty Filter

The filter of an AC is an extremely important component to maintain clean airflow, free from pollutants and dust.

If the air filter is clogged, it restricts the flow of air and decreases the efficiency of the air conditioning system.

Besides, a dirty air filter reduces the AC’s ability to cool the room.

Do read the manual carefully to check the recommendation of the filter manufacturer about air filter and, when to clean or change it.

10. Frozen Evaporation Coil

If the evaporation coil of the Ac is frozen, it might stop working. It happens when the AC does not receive adequate air to operate properly.

A frozen evaporation coil makes the AC freeze up and stops functioning completely. Often, you may even find ice accumulated on the coil.

Inspect the damage and diagnose the problem. Allow the evaporator coil to defrost. You can do it by giving a break to the unit.

Ensure that the power is disconnected. In 24 hours, the evaporator coil would defrost completely.

If the frost is moderate, you can keep the system running on its fan mode as the blower fan melts the frost without turning the unit off.

In the worst case, you would have to call an HVAC expert.

11. Electric Coil Failure

Sometimes you may turn the air conditioner on/off so frequently that the fan and compressor of the system wear out.

The condenser motor, blower motor, and compressor are all connected to make a connection and start the air conditioner unit.

Any disruption in connection due to wire corrosion or any of the terminals prevents the motor and compressor from turning on.

Check all electrical connections to determine the issue.

See professional help. Regular AC maintenance is the only way to prevent these problems.

12. AC Fan Failure

The outer unit of an air conditioner operates to transfer the heat from indoors to outdoors through the fan located in it.

If the fan located in the outdoor unit does not perform up to the mark, it would not allow adequate heat transfer.As a result, the compressor of the air conditioner may overheat or might even trip. Worst of all, it may damage the compressor internally and you may need a replacement.

If the fan stops, you should inspect the wiring of the system or loose components. Just remove the outer casing to inspect the issue visually.

Again, make sure you turned the power off before doing this.

Although it may not be possible to diagnose the issue, you can give it a try, and then call an HVAC expert.


An air conditioner could have one or more problems during the peak summer season. It is very important to maintain the air conditioner to avoid such problems, which could lead to irreparable damage and loss.

With this handy information about air conditioners and possibilities of problems, you can safely assess the condition of the unit and get it checked sooner.

Air conditioners last long when maintained properly. Regular maintenance increase efficiency and reduces risks of failure.