A heat pump is an energy-efficient option for heating and cooling your Conroe area home. Heat pumps perform well in climates with hot summers and relatively mild winters, so they’re well suited for our area. Before you finalize plans for your new construction or renovation project, consider the pros and cons of heat pumps, as well as conventional furnaces and central air conditioning systems.
How a Heat Pump Works
A heat pump heats or cools your home by moving heat from one place to another. During the summer, the system extracts heat from inside your home and moves it outside. In the winter, the system is reversed so that heat is drawn from the outside air and moved to the inside. The heat pump accomplishes this with a refrigerant circulated by an electric pump and compressor through heat exchanging coils inside and outside your house.
In heating mode, the outdoor coil acts as an evaporator, transferring heat into the refrigerant, which circulates through the indoor condensing coil where it gives up its heat inside the house. In cooling mode, the system is reversed so that the outdoor coil is the condenser and the indoor coil is the evaporator.
Since heat pumps move heat using a small amount of electrical energy rather than generating heat by burning fossil fuels as a conventional furnace does, they actually deliver more heat energy to the home than they consume in electrical energy required to move the heat. Modern heat pumps can deliver three times as much heat as they consume in electricity, whereas a highly efficient furnace is always less than 100 percent efficient due to heat lost up the flue with the combustion gases.
Heat Pump Pros and Cons
Heat pumps have advantages and disadvantages compared to conventional systems using a fossil fuel furnace and a central air conditioner. Here are some considerations to discuss with your architect and HVAC contractor as you plan your new heating and cooling system:
- Reduced energy costs – Heat pumps heat and cool using much less energy than conventional systems. Because they move heat rather than generating heat through fuel combustion, they can heat a home in a moderate climate much less expensively than a traditional furnace can.
- Initial cost – Heat pumps can be less expensive upfront than conventional furnace-plus-air conditioner setups because the heating and cooling equipment is combined into a single unit. But, even in mild winter climates like that of Conroe, heat pumps need a backup heat source during very cold weather. Backup heating can be provided by electric resistance heating coils built into the air handling system or with a small fossil fuel-burning furnace. Electric heat isn’t as efficient as a furnace, but the equipment for electric backup heating is cheaper than installing a backup furnace.
- Poor cold weather performance – As the temperature drops below about 40 degrees, a heat pump loses its effectiveness because the amount of heat that can be extracted from the outside air is offset by heat losses from the home. One solution to this problem is to install a ground-source, or geothermal, heat pump, which takes advantage of the relatively constant temperature a few feet below the surface of the ground. Geothermal systems are more expensive to install than air source heat pumps, but their extra cost can be recovered through reduced energy bills.
- Summer indoor humidity control – In cooling mode, a heat pump dehumidifies the indoor air as effectively as a traditional air conditioner. It’s important to size the heat pump for the expected cooling load so that it runs for extended periods rather than short cycling. Proper sizing will optimize indoor air quality and lead to longer equipment life.
- Noisy operation – The outdoor unit of a heat pump is just as noisy as a conventional air conditioner, so you should plan placement of the unit with the comfort of your neighbors in mind.
- Proper installation is critical – Although heat pumps have been around for a long time, some heating and air conditioning technicians aren’t as familiar with their installation and operation as they are with conventional systems. Correct refrigerant charge is crucial to the efficient operation of the system, so be sure your technician is up-to-date on the latest standards for heat pump installation and maintenance.
Have more questions about the heat pump? Contact the HVAC experts at Conroe Air for more design, installation and maintenance tips related to your home’s heating and cooling systems.