What is an Air Source Heat Pump?
An air source heat pump is a highly efficient heating and air conditioning system that can deliver one to three times more heat than the electricity they consume. Their efficiency stems from their ability to move or transfer heat from the air versus traditional systems, which must convert it from a fuel source.
Until recently, air source heat pumps were used primarily in the southern regions of the United States due to homes with mild climates that do not need huge heating capabilities. However, advances in the technology have allowed heat pump units to offer a viable space-heating alternative in colder regions of the country versus electric resistance, or gas and oil furnace heat systems. An air source heat pump can work on its own or by also installing a gas furnace unit. Because the system assumes some of the heating load, the backup furnace system operates less frequently which increases overall efficiency of your home and reduces energy consumption and costs.
When deciding to install an air source heat pump, you have two options. If you have existing ductwork in your walls and attic, you can easily replace your current HVAC system with a central ducted air source heat pump.
If you will need to install ductwork and vents in your home, it may be more affordable to install a ductless mini split heat pump system instead. A ductless heat pump does not need your home to have ducts or vents to heat or cool your home. However, you will have to plan certain zones and get a heat pump that can handle your cooling and heating needs. Air source heat pumps are much more affordable than installing a geothermal heat pump type.
Central Ducted Air Source Heat Pumps
A ducted air source heat pump incorporates a circuit of air ducts and vents that circulate and transport conditioned air throughout the structure and back to the system. Ducted systems are most often used in new construction or when replacing outdated equipment in homes that already have a duct system in place.
Ductless Mini Split Air Source Heat Pumps
Ductless mini split heat pump systems offer broad versatility as they require zero ductwork. A simple, three-inch hole bored through an exterior wall is the only home modification required. The hole is necessary to provide access for the copper suction lines, drain line and wiring between the two components. Ductless systems are ideal for room additions and garage applications where a separate heating or cooling system might be desirable. They also offer a convenient way to increase or supplement existing heating and cooling in areas of your home that may be lacking.
What Size Air Source Heat Pump Do I Need?
Depending on the size of your home or the rooms you are needing to cool and heat, you will want to install an air source heat pump that has the ability to efficiently maintain your home’s temperature. For a 400 square foot area needing to be cooled or heated you will want an air source heat pump able to produce 9,000 BTUs. You can see our full chart for room size and BTU capabilities needed below:
|Ductless Heat Pump BTUs Needed||Room Square Ft.|
|6,000 BTUs||150 to 250 sf.|
|7,000 BTUs||250 to 300 sf.|
|8,000 BTUs||300 to 350 sf.|
|9,000 BTUs||350 to 400 sf.|
|10,000 BTUs||400 to 450 sf.|
|12,000 BTUs||450 to 550 sf.|
|14,000 BTUs||550 to 700 sf.|
|18,000 BTUs||700 to 1,000 sf.|
|21,000 BTUs||1,000 to 1,200 sf.|
|23,000 BTUs||1,200 to 1,400 sf.|
|24,000 BTUs||1,500 sf. +|
Single vs Multi Zone Air Source Heat Pumps
Single zone systems rely on one outside condensing unit and one inside evaporating unit, which is referred to as a head. These air source heat pump systems are ideal for single applications such as room additions, garages, or small workshop spaces.
Multi zone systems are those systems capable of supporting several inside air handler units with a single heat pump condensing unit outside. These systems are installed in homes to provide heating and cooling versatility. A multi-zoned system allows the user to cool specific areas of their home with different temperatures in each room or zone instead of the entire home space being the same temp. This can reduce energy consumption and lead to significant savings on your monthly utility bill. A simple explanation to describe a multi split air conditioner vs a single split AC zone system can be found here.
How Do Heat Pump Works?
Traditional air conditioning systems rely on electrical resistance heating elements to warm the air. This is not the case with air source type of heat pump systems, which uses a much more energy efficient means to produce the heat. When the temperature drops, a programmed thermostat calls on the system to produce heat. The system powers on and liquid refrigerant begins to pass through the condensing coils absorbing heat from the outside air. The refrigerant then converts or evaporates into a gas. It is possible to draw heat from outside air even during the cold winter months. Once the gas travels through the system and back to the inside evaporator coil, the heat is released and the gas is converted back into a liquid refrigerant and returns to the condensing coil where the whole process starts over.
The system uses a fan and blower assembly to distribute the conditioned air throughout the home. As fresh air is drawn back into the system through its return vent, it passes through the evaporator coil where it is reheated. The process is repeated continuously until the desired comfort levels are met.
A heat pump system is also capable of cooling by utilizing a reversing valve that changes the direction of the refrigerant flow. The reversing valve is also used as a means to defrost the condensing coils during the winter months when necessary.
Heat Pump Labor Installation Costs
For labor costs, you can expect most heat pump installers to charge anywhere from $68 t0 $150 per hour. This will largely depend on the amount of contractors it takes to complete the job and the competitive local installation service rates that are common for HVAC contractors in your area. Expect the average heat pump installation to take up to 20 hours for a brand new system with ductwork. It can take much less time to install if you are simply replacing a heat pump system or repairing your current one.
Comfort and energy efficiency are the biggest advantages of a new air source heat pump system. But if your heat pump unit is installed incorrectly or is not the right size, you will not experience either of those benefits.
Unless you are a builder or remodeler, it is worth hiring a ductless air conditioner installer with the right tools in their belt. The contractor has to lay concrete for the outdoor unit, cut a hole in the exterior wall, run the electrical lines for the conduit, and perform other tasks as needed, such as getting rid of some of your current system’s components. Expect to pay between $1,300 and $2,000 for the whole installation.
While you may be tempted to settle for the best price for a heat pump installation regardless of specific experience, remember that ductless heating and cooling systems are still a niche market in the U.S. You may have to hunt a little for the right contractor, so do not settle for someone you are not sure will do a good job just because they offer the best price.
What to Know Before Installing a Heat Pump
Place the condensing unit away from areas around your home, such as bedroom windows and patios where its operation could produce noise and create a problem. Keep in mind when placing your condensing unit it should be in a protected area away from high winds which could negatively affect its defrost cycle. Only hire licensed and insured air source heat pump contractors to install your system. Ask for references and follow up by contacting the Better Business Bureau to inquire about any complaints. Find heat pump installers near you and read recent homeowner reviews to hire the best contractor in your area.