How Does a Heat Pump Work?
Heat Pumps in Atlanta
A heat pump can be one of the most efficient ways to heat your home. To fully explain how a heat pump works, you must first understand how an air conditioner works. The reason is that a heat pump in the heating mode is simply an air conditioner working in reverse. The main factor to consider when talking about heat pumps or air conditioners is to remember both units simply move heat. Before we begin, let’s talk about the components of both the heat pump and the air conditioner.
As you see in the graphic to the right, the heat pump and the air conditioner are practically the same. Let’s break each component down:
- Compressor – this “compresses” the refrigerant and increases its pressure. Increasing the pressure of the refrigerant is critical since as the refrigerant passes through an expansion orifice in the evaporator (3) or condenser (2) the pressure very quickly reduces. Thanks to physics – when a gas rapidly expands, it absorbs heat like a massive sponge.
- Condenser – coil that absorbs or releases heat depending on which mode the heat pump is in. In the heat mode the condenser becomes a “heat sponge” grabbing all the heat from the outside air as the refrigerant expands through the expansion device. It then sends this heat to the evaporator (3) to be released into your home as a fan blows air across it. In the cooling mode, the condenser becomes a “heat dumper” and as the outdoor fan blows air across the coil, heat is released outside.
- Evaporator – coil that absorbs or releases heat depending on which mode the heat pump is in. In the heat mode, the evaporator acts as a “heat dumper” releasing heat to the indoor air as your indoor fan blows air across it. In the cooling mode, the evaporator again uses physics to become a “heat sponge” grabbing all the heat from the indoor air as the fan blows the air across the evaporator.
- Air handler – Indoor fan that blows air across the evaporator and into the ducts of your home. In the heating mode, the air handler is releasing the captured heat from the outside and in the cooling mode it is grabbing heat from the indoors and then moving it outside.
- Reversing valve – this is the valve that switches the heat pump back and forth between the heating and cooling mode. In the air conditioning mode, the valve directs the refrigerant so that it captures heat from the inside and moves it outside. In the heating mode, it directs the refrigerant so that it captures heat from the outside and moves it inside your home.
The heat pump is actually quite efficient at grabbing the heat from the outdoors and moving it inside. When the outdoor ambient air is above 40 degrees Fahrenheit, the heat pump is the most cost effective way to heat your home. When the outdoor ambient air drops below 30 degrees there is not enough heat in the air for the heat pump to grab and many times a back-up heat source is required to provide your home with heat. Electric heat strips can prove this back up heat source if your home is total electric. The most efficient way to provide this back-up heat however is to install a 90% furnace to provide back-up heating. When a heat pump is installed with a back-up fossil fuel furnace the combination is known as a dual fuel system. A dual fuel system provides the most efficient way to heat and cool your home and the energy savings each month will more than offset the initial investment of having a new high efficient dual fuel system installed.
Empire Heating & Air Conditioning offers many types of heat pumps and dual fuel systems. Click here to view all of our new HVAC products. We are currently offering discounts on select new systems. Save up to $1, 950 with federal energy tax credits, manufacturers’ rebates, instant savings, and Georgia Power Incentives. Call Empire today at 404-294-0900 to schedule your free consultation.