Understanding Heat Pump Defrost Cycle – Is It Normal?

Most heat pumps have features that increase their efficiency during freezing weather. When it starts to freeze over, you might notice that your heating unit stops blowing warm air for some time. The indicator lights blinking means that the heat pump is in the defrost cycle. This is a normal process and there is nothing to worry about.

The heat pump defrost cycle is the process by which the thawing process occurs if the heat pump is operating with a frozen coil. The defrost cycle removes ice buildup from the coil and thaws it, which is necessary to prevent damage to the equipment or injury to the homeowner.

As the temperature falls outside, the outdoor coils of the heat pump are exposed to the outside temperature. Gradually, the outdoor coils start to freeze and the heat pump will go through a defrost cycle. The goal of the process is to unfreeze the coils so that they can be used again, and the heat pump will be ready to start again.

What Is Defrost Mode on a Heat Pump?

Defrost mode is the setting on your heat pump that turns the heat pump into a defrost system. When the outdoor units are in defrost mode, they remove the buildup of ice on the coils, which needed to be defrosted before the system can be used again.

How Does a Heat Pump Defrost Cycle Work?

As the heat pump enters the defrost mode, the indicator lights will start blinking. This will happen faster when the heat pump is in the defrost mode than it does when it is in the normal mode. The heat pump will start to blow warm air, which will turn off when the heat pump turns off the fan. The heat pump will turn back on and go through the defrosting process again when it is time to turn back on.

How Long Should a Heat Pump Run in Defrost Mode?

A typical heat pump defrost cycle runs for 30 seconds to a few minutes, depending on the model and how long the heat pump has been in defrost mode. A short defrost cycle will happen in a matter of minutes, especially when the heat pump is new and the coils are still cold, whilst a long defrost cycle may take hours, given that the heat pump has been in use for some time.

What Causes Your Heat Pump Defrost Cycle to Stop Working?

The defrost mode on your heat pump can stop working completely or it can stop working after a few minutes. There are several reasons why this can happen.

Faulty Sensors, Reverse Valves, or Thermostat:

The heat pump defrost cycle may stop working due to sensor faults, reverse valves, or thermostats. A faulty reverse valve may create a situation where the heat pump is not putting out enough heat. A faulty thermostat or reverse valve may cause the heat pump to turn on and off frequently, which will cause the defrost cycle to stop working. Call upon a heat pump expert for heating repair in Brooklyn.

Refrigerant Leaks:

One of the most common causes of the heat pump defrost cycle stopping working is when refrigerant leaks occur. Refrigerant leaks can occur due to a faulty refrigerant recovery valve or refrigerant lines. When refrigerant leaks occur, they cause the heat pump to stop working, which will cause the defrost mode to stop working. The heat pump should take to a HVAC repair specialist to find the leak and correct it.

Electrical Issues:

Over time, electrical components can wear out and stop working, preventing your HVAC system from signaling the defrost mode to turn on. The most common electrical issues that cause the defrost cycle to stop working are when there is a fault with the defrost sensor. When the defrost sensor faults, the heat pump will continue to defrost the outdoor unit, even though it is not meant to be in defrost mode. This will cause the heat pump to stop working. Hire an expert for heating repair in Manhattan today.

Other issues include improper installation, damaged or broken coils, clogged units, and malfunctioning sensors.