You are relaxing at home and hoping to spend a good, quiet evening in summer, and then, clunk, buzz, rattle! Your air conditioner has new music, and you did not request it.

The sound of noisy AC can be irritating, but above all, it tends to be your system giving you a sign that, “Hey, something is not right.” So, this is what these weird sounds may mean, and when you should start calling professionals.

Banging or clunking

When it sounds like there is something dropping and banging around in your AC, then there is a possibility that there is a broken or a disjointed portion of the system, such as a rod or piston within the compressor.

In other cases, a fan blade might be misaligned and strike other objects. In any case, it is not something to overlook. Shut off the unit and schedule an air conditioner repair before any additional damage.

Buzzing or humming

You should not always worry about a light hum; this might be the usual noise of the motor. However, when the buzzing is so loud or sharp, it might indicate:

• Loose wiring
• Dying motor
• Leakage in refrigerant
• Obstructions in the outside unit.

You have the option of inspecting around the exterior unit to dislodge any leaves/twigs you see protruding there. However, if the buzzing persists, it is better to leave it to the experts, particularly when electrical problems are at play.

Screaming or squealing

This is a difficult one not to hear. It may even seem that your AC is crying. Screeching nearly always signals:

• A tired-out fan belt (in older systems)
• Failing motor bearings
• High internal pressure in the compressor.

Whichever it is, don’t let it run out that way too long. This sharp screeching may result in more extensive repairs to the system or a complete system failure.

Clicking

It is common for your air conditioner to have just a single click at the time of system start-up or shutdown. However, when it keeps clicking, it is out of order. You may be facing:

• Problems with the thermostat
• A blown capacitor
• Electrical relay problems.

Although this does not sound like a lot, repetitive clicking might indicate an underlying electrical issue. It is advisable to get it checked early enough.

Whistling or hissing

This noise may indicate that you have a leakage, such as air and refrigerant. A whistle that seems to be light may be due to a loose seal or vent. But such a loud, persistent hissing? That may be a sign that your refrigerant is leaking, which is wasteful and hazardous.

Never attempt to work on refrigerant leaks. Contact an accredited HVAC specialist.

Final thoughts

You do not need to be an AC expert to realize that something is off. Listen to your gut. When your unit begins to make sounds that are new or unusual and you cannot quickly justify this change, turn off the machine and call in a repair expert.

It is a quick fix at times. On other occasions, it is an indication of wear and tear accumulated over some period. Either way, early detection will spare you much more costly repairs or a complete overhaul down the line.