Timed defrost and demand defrost: what is the difference

There are different strategies for initiating defrost. The two main ones are timed defrost and demand defrost.

Timed defrost

Defrost starts after a predetermined operating time, regardless of the actual ice thickness.

Demand defrost

The decision is based on actual sensor readings and system behavior.

Advantage of demand defrost

It can reduce unnecessary defrost cycles and improve seasonal efficiency.

Practical significance

In modern inverter units, more sophisticated logic is typically used rather than a simple timer.