Did you know there is a way to heat or cool your home that will save energy and keep more money in your pocket?

No? Well, let us fill you in!! Heat pumps offer an energy-efficient alternative to furnaces and air conditioners, and should be taken into serious consideration. Energy efficiency is the key to everything. It’s what homeowners want. With heat pumps, electricity is used to move heat from a cool space to a warm space, making the cool space cooler and the warm space warmer. Because they move heat rather than generate heat, heat pumps  provide equivalent space conditioning at as little as one quarter of the cost of operating conventional heating or cooling appliances.

According to the experts, heat pumps are greatly beneficial to houses that have an electrical heating system. When the system calls for heat, the cooling system turns into reverse. The compressor outside now acts as a heater so instead of taking the hot air out of your home, it puts it in by compressing the heat and pushing it back inside.

There are several different types of heat pumps. Certain types work better in certain climates, so finding the right one for you should be the first step. 

Types of Heat Pumps

Air-Source Heat Pump 

An air-source heat pump transfers heat between your house and the outside air using electricity. It is also the most common type of heat pump. If you heat with electricity, a heat pump can reduce the amount of electricity you use by as much as 30% to 40%. High-efficiency heat pumps also dehumidify better than standard central air conditioners, resulting in less energy usage and more cooling comfort in summer months. However, the efficiency of most air-source heat pumps as a heat source drops dramatically at low temperatures, generally making them unsuitable for cold climates, making this kind of heat pump a great option for Houston homes!

Its refrigeration system consists of a compressor and two coils (inside and outside) made of copper tubing which are surrounded by aluminum fins to help with the heat transfer. In heating mode, liquid refrigerant in the outside coils extracts heat from the air and evaporates into a gas. The indoor coils then release heat from the refrigerant as it condenses back into a liquid. A reversing valve, near the compressor, can change the direction of the refrigerant flow for both cooling and defrosting the outdoor coils in winter.

When outdoor temperatures fall below 40°F, a less-efficient panel of electric resistance coils, similar to those in your toaster, kicks in to provide indoor heating. This is why air-source heat pumps aren’t always very efficient for heating in areas with cold winters. Some units now have gas-fired backup furnaces instead of electric resistance coils, allowing them to operate more efficiently.

Geothermal Heat Pump

Geothermal heat pumps have been in use since the late 1940s and work in a unique way. With these, the constant temperature of earth is used as the exchange medium instead of the outside air temperature. According to the Department of Energy, this allows the system to reach fairly high efficiencies of 300% to 600% on the coldest winter nights, compared to 175% to 250% for air-source heat pumps on cool days. This means that if you live in a place where temperature drops significantly, this might be the solution for you and your home. 

Even though different places have different seasonal temperature extremes, the ground still remains at a relatively constant temperature a few feet below the earth’s surface. This ground temperature is warmer than the air above it during the winter and cooler than the air in the summer. The GHP takes advantage of this by exchanging heat with the earth through a ground heat exchanger. As with any heat pump, geothermal and water-source heat pumps are able to heat, cool, and, if it has the right equipment, can also supply the house with hot water. Some models of geothermal systems are available with two-speed compressors and variable fans for more comfort and energy savings. When compared to air-source heat pumps, they are quieter, last longer, need little maintenance, and do not depend on the temperature of the outside air. 

Ductless Mini-Split Heat Pump

Ductless mini-split-system heat pumps make good retrofit add-ons to houses with “non-ducted” heating systems, such as hydronic (hot water heat), radiant panels, and space heaters. They can also be a good choice for room additions where extending or installing distribution ductwork is not feasible, and very efficient new homes that require only a small space conditioning system. 

Like standard air-source heat pumps, mini splits have two main components: an outdoor compressor and an indoor air-handling unit. A conduit, which houses the power cable, refrigerant tubing, suction tubing, and a condensate drain, links the outdoor and indoor units together. Two great advantages of mini splits are their small size and flexibility for heating and cooling individual rooms. With this, only occupied rooms need to be conditioned, which saves energy and of course, money! Also, being ductless means that it avoids the energy losses associated with the ductwork of central forced air systems. According to the DOE, duct losses can account for more than 30% of energy consumption for space conditioning, especially if the ducts are in an unconditioned space such as an attic.

Absorption Heat Pump

Absorption heat pumps are essentially air-source heat pumps driven not by electricity, but by a heat source such as natural gas, propane, solar-heated water, or geothermal heated water. Because natural gas is the most common heat source for absorption heat pumps, they are also referred to as gas-fired heat pumps. There are also absorption (or gas-fired) coolers available that work on the same principle. Unlike some absorption heat pumps, however, these are not reversible and cannot serve as a heat source.

Residential absorption heat pumps use an ammonia-water absorption cycle to provide heating and cooling. As in a standard heat pump, the refrigerant (in this case, ammonia) is condensed in one coil to release its heat; its pressure is then reduced and the refrigerant is evaporated to absorb heat. If the system absorbs heat from the interior of your home, it provides cooling; if it releases heat to the interior of your home, it provides heating.

The difference in absorption heat pumps is that the evaporated ammonia is not pumped up in pressure in a compressor, but is instead absorbed into water. A relatively low-power pump can then pump the solution up to a higher pressure. The next task is to remove the ammonia from the water, and that’s where the heat source comes in. The heat basically boils the ammonia out of the water, starting the cycle over again. Although mainly used in industrial or commercial settings, absorption coolers are now available for large residential homes, and absorption heat pumps are under development. The 5-ton residential cooler systems currently available are only designed for use in homes around 4,000 square feet or more.

Absorption coolers and heat pumps usually only make sense in homes without an electricity source, but they have an added advantage in that they can make use of any heat source, including solar energy, geothermal hot water, or other heat sources. They are also amenable to zoned systems, in which different parts of the house are kept at different temperatures.

How to Maintain Your Heat Pump

Like all heating and cooling systems, proper maintenance is imperative if you want your system to continue to work efficiently. The difference between the energy consumption of a well-maintained heat pump and a severely neglected one ranges from 10% to 25% (yikes!). 

We recommend that you clean or change the filters once a month or simply as needed. Dirty filters, coils, and fans reduce airflow through the system, which then decreases system performance and can damage your system’s compressor. Make sure to also clean outdoor coils whenever they look dirty. It’s also a good idea to occasionally turn off power to the fan and clean it by removing any clutter from around the outdoor unit. 

Whenever handling important systems in your home, maintenance is something that comes with the territory. You should also have a professional, experienced JW East Mechanical technician service your heat pump at least once a year. Once there, the technician will take care of any and all issues. Some things they will do are:

  • Inspect ducts, filters, blower, and indoor coil for dirt and other obstructions
  • Find and seal duct leakage
  • Measure air flow
  • Measure refrigerant charge 
  • Check for refrigerant leaks
  • Inspect electrical terminals, clean and tighten connections, and apply non conductive coating
  • Lubricate motors and inspect belts for tightness and wear
  • Check on the electric control, making sure that heating is locked out when the thermostat calls for cooling (and vice versa)
  • Make sure the thermostat is working properly

With proper maintenance and operation, your heat pump will work efficiently and safely to give you, your family, and guests maximum comfort when in your home. And hey, if you can save energy and money, what else can you ask for?