Noise

The quieter air conditioners are, the more pleasant they are to have around.
Over the past ten years significant progress has been made in terms of sound proofing, and air conditioning noise levels have decreased considerably.

Noise reduction solutions include: the use of sound-absorbing materials, increasing aerodynamic design, lower rotational speeds and a focus on selection of better designed components (i.e. Fans, Compressors etc).

A number of factors influence the noise level of an air conditioner:

Indoor units

Larger fans run slower, making less noise. A well designed unit makes less noise because the more aerodynamic the air path inside the unit, the better air passes through it. Inverter units reduce the fan cycling because they control refrigeration capacity. When there are sudden noise changes such as a non-inverter unit switching on or off it makes the noise more noticeable. Inverters, however, slowly speed up and slow down making the difference less noticeable.

Room hardness

When a room has less soft surfaces the sound from a unit bounces around the room. In a “soft” room such as a bedroom with carpets, the same unit will seem quieter than if it were installed in a tiled room with no curtains.

Outdoor units

Position, particularly in the line of sight, allows noise emitted from an outdoor unit to carry to your own environment and your neighbour’s.

Placing a unit lower prevents the noise from carrying over walls. Using an inverter prevents stop-starting of a unit and thus the noise level is reduced and the characteristic of the noise is less noticeable.