Heat Pumps: DO’s and DON’T’s

Many of our clients are from northern states where oil and gas-fired furnaces are used for heating. South Carolina has a more temperate climate and heat pumps are used for both heating and cooling. Given the number of questions we get each month regarding heat pumps this article will address those issues.

Typical Heat Pump (Condenser Unit)

Heat Pump

How Does A Heat Work?

Your heat pump relies on heat within the outdoor air to keep your home at comfortable temperatures during winter. The heat pump transfers heat from the outdoors into your home to warm your living areas. The opposite is true for cooling.

What is the Best Fan Speed?

Typically your heat pump functions more efficiently when you set the fan at a higher speed. Setting it at extremely high speeds as it will produce ambient noise and air movement. In extremely cold weather conditions, a properly working heat pump will run almost continuously.

What is Supplemental Heating?

Most heat pumps have supplemental electric resistance heat strips built-in to the system. At below-freezing temperatures the electric heat strips operate more efficiently than the heat pump.

Why use a Smart Thermostat?


The advantage of a smart thermostat is its ability to learn a household’s patterns and adjust heating and cooling according to when a home is occupied or is about to be occupied. This reduces the use of heating and cooling systems when nobody is home for significant periods of time.

What is the Best Temperature for my Heat Pump?

With your prior heating system you may have lowered the temperature when you went to work or at night. Heat pumps reach their peak efficiency by maintaining a set temperature. Find the right setting then leave it alone!


What is Auto Mode?

Auto Mode

If you use Auto Mode your heat pump runs the risk of toggling unnecessarily between heating and cooling. Your heat pump will run most efficiently when set to “HEAT” in winter and “COOL” in summer. Auto Fan is a separate setting, and fine to use highest speed you’re comfortable with, then dial in your preferred temperature setting.

Should I Use the Lowest Fan Setting?

Fan Setting

Strange but true: a heat pump works most efficiently when set to a higher fan speed. So a low setting is generally not recommended.

Heat Pump Maintenance!


Every heating and cooling system needs maintenance. We recommend a service plan that includes servicing every six months. Change your air filters every two or three months. Be sure the outside unit is free of tree branches, leaves, and other debris.

Why do I get Frost on my Condenser Unit?

Your heat pump works in cycles. Periodically, the coil will collect a layer of frost or thin ice when it’s cold outside. At a certain point, the defrost cycle should automatically switch on to keep the pump working normally. As long as the condensing fan motor can pull air into the unit, there is no need to worry about the frost.