Did You Hear That?
Houses and apartments can be the source of so many odd sounds, coming from hidden places for reasons unknown. Most noises are harmless, resulting from structural material expanding and contracting due to temperature variations—nothing to worry about. What types of noises are typical for your air conditioner system and what types of noises should cause AC Repair concern?
Normal Noises
Clicks. When the thermostat recognizes a temperature rise, you might hear a soft click—first at the thermostat and then at various places along the component pathway. Of course, expect another click that indicates the air conditioner has done its job, signaling the end of the cooling cycle.
Startup Sounds
After the thermostat clicks, expect a delay as cooling begins and what has been described as a rapid buildup, not unlike a jet engine startup. The size and materials of the space may determine how much of this is normally heard. This sound is coming from one of the few moving parts, as the blower motor begins to spin rapidly. The “whose” of air movement might also be heard.
Gentle Pops
The ductwork is a network that moves the cool air from the blower motor throughout the house. Ducts are made of rather thin sheet metal, so it is not unusual to hear a few light pops, as the metal contracts and expands.
Abnormal Noises
The decibel level of sound will vary with construction materials, space layout, and brand/age of the air conditioner. Normal noises are heard most of the time and heard consistently. Abnormal noises begin when something happens to the normal air conditioner function. Abnormal sounds include:
Buzzing or Loud Humming
When electrical parts function properly, they give off a soft, perhaps imperceptible hum. When parts begin to wear or are under stress, the hum or buzz increases in volume and may sound menacing. Showing the location of such buzzing to a technician will be very helpful in the diagnosis process.
Whistling
Whistling generally indicates restricted air movement. When an air filter is clogged, air may whistle as it tries to move around the filter. The same sound can be observed if a vent or return is partially blocked, restricting airflow.
Hissing, Bubbling, or Gurgling
The air conditioner functions via the use of refrigerant gas. Under certain conditions, this gas becomes a liquid, so the same substance can be found in the system in one form or another. Whenever the gas/liquid is leaking, you may hear it escaping from the closed system while under pressure. The system contains a relatively small amount of gas, so this noise will not last long. However, locating the source of this sound will be very important to the repair technician.
Screeching, Rattling, or Banging
There are very few moving parts in an air conditioner system. Noises such as screeching, rattling or banging that could be cause for concern may involve the blower motor. Any of these noises will be associated with the blower assembly—imbalanced or loose fan blades for instance. If something besides the blower assembly is making a rattling or banging noise, something is moving that should not move. Locating this sound will be extremely helpful for diagnosing the problem.
Air conditioners, like lighting, make gentle noises that are the background of our life. When something goes wrong resulting in an unusual noise, take note and seek assistance for an AC Repair remedy.
For more information about R.M. Mullinix and our AC repair services, schedule an appointment, or visit our HVAC Maintenance Plan information page.