A window air conditioner unit can provide targeted cooling for a single room. Due to its proximity to the space, though, issues that result in noisy operation can be especially annoying. Repairing the noisy AC problem is a must for both your peace of mind and to ensure that the AC continues to operate properly.

1. Lubrication Issues

Loud squeals and squeaks are often the result of a lack of lubrication on one of the moving parts of the air conditioner. Some window units may have belts that require some lubrication, or the issue could be poor lubrication in the fan assembly or motor. The unit must be opened up so that the necessary lubrication points can be accessed, which is a task best left to a professional.

2. Trapped Debris

Window units can be especially prone to debris getting into the unit. Unlike central units, which are usually placed in a location that provides some protection from debris, a window unit is simply placed in the best window for cooling the interior of the home. This means the outside portion of the unit may be exposed to windblown debris or it could be placed in an area where falling leaves and twigs are likely to get into the unit. A full interior servicing and cleaning of the unit is necessary to get rid of the rattling noises of trapped debris.

3. Damaged Blower Fan

Blower fan damage can cause several different types of noise. A bent fan blade, for example, may cause rattling and vibrations. A failing motor may grind or squeal. Often the noises will occur in conjunction with reduced airflow and cooling. Minor damage, such as failed bearings or a damaged fan blade, can typically be repaired. Damage to the motor itself may require the installation of a new motor.

4. Mounting Bracket Issues

If the whole unit is rattling and vibrating, then the issue may not be with the AC itself but instead with its mounting hardware. It's best to have a unit professionally mounted so that it is firmly anchored to the window frame and properly sealed so that air leaks can't occur. Simply setting the unit in a window frame and using the weight of a window to hold it in place is insufficient.

5. Clogged Filtration and Vents

Clogged filters can cause whining noises or loud motor operation as the entire unit struggles to operate with the reduced airflow. The filter in most units is accessible from behind the interior grill panel, and it should be cleaned monthly. The exterior fan vents must be hosed off once a year. If exceptionally dirty, a professional disassembly and cleaning may be necessary.

Contact an air conditioning repair service if you are having issues with a noisy window unit.