Considering a Heat Pump? Here are the Pros and ConsPublished on: October 25, 2013
Choosing an energy-efficient heating and cooling system for new-home design or system replacement deserves thoughtful consideration. If you’re considering a heat pump as the system of choice for your home, it’s wise to weigh the pros and cons of a heat-pump installation, and explore advanced features and ancillary components which make heat pumps so popular throughout the Southeast region.
How Does a Heat Pump Pump Heat?
Contrary to its name, a heat pump doesn’t actually pump heat. It pumps the refrigerant which extracts, moves and releases heat from one location to another. This may seem like an insignificant point, but it is actually an important point to energy efficiency which separates heat pumps from heating systems that burn fuel to make heat. By using refrigeration principles of moving heat from a warmer place to a cooler place, heat-pump systems generate up to 400 percent more heat-energy than energy consumed.
In the warmer climate of the Southeastern U.S., heat-pump installations have a proven track record for delivering energy-efficient heating and cooling in one system. A heat pump is essentially an air conditioning system that is fitted with a few more components which allow it to provide home heating in addition to home cooling. This is the basic operation of the popular split-system air-source heat pump:
- The compressor squeezes refrigerant to prepare it for heat transfer.
- The hot gaseous refrigerant is pumped to the reversing valve, and directed to one of two heat-exchange coils.
- Depending on the cycle, the refrigerant either releases heat or extracts heat from the heat-transfer medium with the aid of one of two air handlers (one inside the home and one outside the home).
- The airflow across the coil is either cooled or warmed by the extraction or release of heat by the refrigerant.
- The cooled or warmed air is delivered to the living spaces through the air ducts.
Pros and Cons of the Heat Pump
Heat-pump efficiency for moving heat from one location to another is affected by the weather. Homes in colder regions of the U.S. with older heat-pump systems require a backup heating source, such as electric-resistance heating (installed standard with conventional heat pumps), a furnace or a boiler. This is because the extraction, movement and release of heat-energy — refrigeration principles — of heat pumps are affected by the outside temperature.
Older heat-pump systems have a difficult time maintaining efficiency when the temperature of the heat-exchange medium (outside air) falls below the freezing point. For homeowners in the Southeast U.S., this is not a significant issue, and heat pumps offer many more positive attributes than negative ones.
In fact, advances in technology to promote more efficient heat exchange are delivered in every major component of new heat pumps, providing ample heating when outside temperatures fall well below the freezing point. These are more pros of choosing a heat-pump system:
- Heat pumps offer efficient cooling and heating in one system, which means less maintenance and upkeep compared to separate systems for heating and cooling.
- Variable-speed compressors and variable-speed air handlers offer precise cooling and heating output to the home’s load.
- Compressors are much quieter and more durable for a longer life span and fewer maintenance issues.
- High-efficiency refrigerant (R410A) is ozone-safe, and delivers much greater super-heating and super-cooling capacity than the outmoded R22 (Freon).
- Heat pumps may be installed to heat pools and spas.
- A desuperheater (add-on heat-exchange coil) provides efficient water heating for storage water-heating systems at much less energy costs than electric water heating by using excess super-heated gases from the heat pump.
- Use the sun’s energy to go green by installing your heat pump as part of a solar-electric system.
- Heat pumps may be combined with a furnace for a powerful and efficient dual fuel heating system, alternating between energy sources to maximize efficiency. And, you may still enjoy the cooling efficiency of the heat pump during the cooling months.
- Geothermal heat pumps last for decades, providing a stable and free energy source for heat exchange.
- In addition to the affects of very cold weather on heat-pump efficiency, installation is a common factor for under-performing heat pumps. Make sure you hire a reputable HVAC contractor to accurately size and install your new heat pump.
- The outside cabinet of air-source heat pumps requires occasional attention to make sure nothing blocks free airflow, such as debris, leaves, snow and ice (whereas a furnace and boiler are completely protected inside the home).
For more pros and cons of installing a heat pump, contact AC Southeast® to locate a contractor near your Southeast U.S. home.