Home heating and cooling can consume a substantial portion of a residential budget, so many homeowners look for the best and most efficient option when upgrading or installing a new HVAC system. Heat pumps offer extremely high levels of efficiency with low operating costs that can slash both heating and cooling expenses by a significant percentage. Here’s a brief overview of these systems and the many heat pump advantages that make them a wise investment.
How Do Heat Pumps Work?
One of the most important heat pump advantages is the way the systems work. They operate on the principle of capturing heat and moving it from place to place, taking it away from where it’s not needed and bringing it to areas where it’s wanted. This type of heat movement results in high levels of indoor comfort while also providing extraordinary efficiency. Air-source heat pumps, the most common type, use the air around the indoor and outdoor units as sources of heat acquisition and dispersal.
Heat pumps consist of two sets of components. One is installed inside your home and the other set is housed in a cabinet outdoors. The outside cabinet is usually installed close to an exterior wall. The two sets of components are connected via electrical cables and refrigerant lines containing the substance that allows heat capture and release to occur.
Taking cooling functions as an example, a heat pump starts with liquid refrigerant in the indoor unit. In the evaporator, the liquid refrigerant is converted to a gas. During this change of state, the refrigerant absorbs significant amounts of heat from the air around the indoor unit. This process creates the cool air that’s circulated through the ductwork and into your home’s interior by the air handler’s fans.
The hot gaseous refrigerant is then circulated to the outdoor unit by the compressor. The refrigerant enters the condenser. With additional pressurization provided by the compressor, the gaseous refrigerant changes state again, this time back to its liquid form. When the refrigerant becomes a liquid again, it releases the heat it contains. The heat is then dispersed into the air surrounding the outdoor unit. The liquid refrigerant then circulates back to your home and into the indoor unit, where the heat capture and release process begins again.
When the heat pump produces heating, the process is reversed. The refrigerant changes to a gas and absorbs heat from the outdoor air, then releases that heat indoors. A heat exchanger transfers the heat to the air that is blown into your indoor spaces to create warmth.
Heat pumps can pull sufficient amounts of heat from even cool outdoor air with temperatures down to about the freezing point or somewhat above. When temperatures fall below this level, however, heat pumps can’t function effectively. Supplemental heating coils activate to produce heating until outdoor temperatures sufficiently rise.
This process eliminates much of the efficiency advantage of a heat pump, but it’s usually temporary. Heat pumps aren’t recommended for climates where temperatures frequently drop to freezing or stay there for an extended period when they do.
Heat Pump Advantages You Can Expect
When you install a heat pump, there are several important heat pump advantages you can reasonably expect. They include:
- Extremely high efficiency: Heat pumps have a well-deserved reputation for being extremely energy efficient. In fact, they can produce levels of efficiency that seem to defy logic. For example, during heating operations, a heat pump can move three, four or sometimes more units of heat for each unit of electricity consumed by the equipment. This results in an astounding 300 to 400 percent efficiency level for heating functions. This is possible because the heat pump moves heat that already exists instead of burning fuel or consuming electricity to generate heat. Cooling operations don’t achieve these extreme levels of efficiency, but they are still more efficient that similar cooling functions from an air conditioner.
- Minimal operational costs: One of the main heat pump advantages resulting from high efficiency is the low cost required to run. Heat pumps can slash your monthly heating and cooling costs by a significant percentage — often 40 percent or more. The savings can be so impressive that homeowners can recover the cost of their initial investment in the heat pump within a few years, and certainly by about the halfway point of the system’s expected functional life span. Equipment that pays for itself over time is one of the biggest heat pump advantages that buyers find most attractive.
- Environmentally friendly function: Since heat pumps don’t burn fuel or consume electricity to create heating or cooling, they place less of a burden on local utility companies that provide gas, electricity and other power sources. They also do not generate any greenhouse gases or potentially dangerous by-products, such as carbon monoxide. In general, heat pumps can help reduce the amount of these substances produced by utility companies.
- Virtually silent operation: Heat pumps operate very quietly, with considerably less noise than comparable heating and cooling systems. This makes them a much better choice for homeowners who could be annoyed by loud sounds coming from the HVAC equipment.
Sizing a New Heat Pump
Heat pumps must be properly sized to ensure they provide the amount of cooling and heating you need for your home. Sizing refers to the equipment’s functional capacity and its ability to heat and cool your home to your preferred temperature. Too small and the system won’t be able to keep up with indoor comfort demands. It will also work too hard and wear out sooner. A system that’s too large will waste energy and money by producing more heating and cooling than needed.
Have your HVAC professional perform a load calculation to determine exactly how much heating and cooling your home needs. This sophisticated assessment takes into account physical and thermal characteristics of your home’s structure and your own individual requirements for home comfort. The results of a load calculation will tell your HVAC contractor how much heating and cooling is needed and will allow him to direct you to a heat pump that will provide it. Use industry standard techniques for the load calculation, such as those in the Air Conditioning Contractors of America’s Manual J, “Residential Load Calculation.”
Look at Efficiency Ratings Before Choosing a New Heat Pump
Heat pumps will have numerical ratings that indicate their efficiency. In most cases, it’s advisable to purchase a system with the highest efficiency rating possible. Heating operations are rated by the heating seasonal performance factor, or HSPF. Cooling functions are rated by the seasonal energy efficiency ratio, or SEER. High-efficiency systems will usually have an HSPF between 8 and 10 or higher and a SEER between 14 and 18 or higher.
Heat pumps and other types of HVAC equipment should have their efficiency ratings and other important information displayed on the EnergyGuide label. This bright yellow label will usually be affixed to the outside of the equipment and will contain relevant data on efficiency, energy use and projected operation costs.
You can also look for the Energy Star logo on your new or replacement heat pump. This symbol indicates that the heat pump model has been thoroughly tested and has met government standards for high efficiency.
Heat Pump Maintenance
Once you’ve enjoyed the many heat pump advantages, you’ll want to do everything possible to ensure you continue to benefit from them for years. Regular preventive maintenance is the most important way to sustain the performance and efficiency of your heat pump system.
Contact your local trusted HVAC professional for a preventive maintenance inspection at least twice a year — once in the spring and once in the fall. Maintenance will keep the equipment working at its best level of efficiency and effectiveness and will extend the life of the system. It will also help prevent malfunctions and breakdowns that could result in costly repairs.
For more information on heat pump advantages that can improve home comfort and reduce overall costs, check out Griffith Energy’s heat pump solutions, or give us a call at 888-474-3391.
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