Steam Coming Out From Outdoor Unit

Seeing the outdoor unit making loud noises and the steam coming out of the system without the motor running but this steam may not be coming because of any problem this might be your unit going to the defrost system.

Heat pumps go under defrost mode generally in cold winter months. Heat pumps extract heat from the outside and supply them inside the house during the winter season. This system works well until the outside temperature drop downs nearly to freezing point.

At the freezing point the outdoor unit can actually start to freeze to prevent the unit from freezing. To prevent the unit from freezing heat pump goes into the defrost mode and turns the air conditioner on for few minutes at that time heat is supplied outside.

You will not fell cool inside because of the auxiliary heater present inside the air handler. After the defrost procedure is complete the heater will start again.

When the unit goes under defrost mode outdoor fan is stopped to create more heat, when air conditioner is turned on outdoor unit works as the condenser. The refrigerant flows through the coil during this procedure heat flows from the auxiliary heater to prevent the cold air from reaching the house.

When the heat blows on the coils the ice starts to melt and from a liquid it changes to gaseous state. The steam which you see coming out your system is actually the water formed due to defrost cycle.

Your heat pump will go in defrosting regularly in winter season there is no harm in that it is a good thing heat pump defrost to increase the efficiency of the unit.

If it is not cold and unit goes under defrost mode when ever required to melt the ice formed and prevent the unit from any damage. If your unit is going under defrost mode regularly this might indicate that there is a problem in your unit.

There are several reasons why this could happen

• Bad defrost control
• Defective defrost thermostat
• Broken outdoor fan
• Blocked outdoor coil
• Low refrigerant.