Mini Split Airconditioners. Defrost Cycle.

During winter months many heat pumps will need to go through a “defrost” cycle during operation. Often this has not been explained well before installation, which leads to a lot of confusion about why the heat pump is not working. This document is provided to help users understand the defrosting cycle and address any concerns.

Mini Split Airconditioners Reviews. What is a “defrost cycle”?

In heating mode a heat pump extracts heat from the outside air and transfers it inside your premises to warm it. When the ambient temperature outside gets very cold (close to 0°C or below) the moisture in the air freezes on the outdoor unit’s heat exchanger as the fan blows the air across it. A defrost cycle is simply the system recognising that ice has formed or begun to form and automatically fixes this.

Airconditioners Ductless. Why does my unit have to do a defrost cycle?

Any ice building up on the outside heat exchanger reduces the airflow across it, which will affect the efficiency, sometimes reducing it dramatically. In extreme cases this can also cause damage to the outdoor unit.

Portable Airconditioners. How do I tell if my unit is in a defrost cycle?

Inside you will notice the unit will stop heating, the indoor fan will stop and depending on the model there will usually be some form of visual indication like a light on the unit (usually the “run” light) will blink continuously. Outside, the outdoor fan will also have stopped and the compressor will be running.