heat pump types

Trane Air Source Heat Pump Condenser

Heat Pump Types - There are different types of heat pumps available on the market today. A heat pump is an air conditioning unit that cools when the temperature is hot and heats when it is cold. There are many different types of these heat pump systems available. There is the geothermal heat pump. It can either utilize a series of closed-loop water pipes buried in the ground or other methods of heat exchange.  This process removes or absorbs heat for heating and cooling.

Air source heat pumps can be configured differently. One type of air source heating will utilize electric heating for backup heating while another may use a gas furnace for backup heating. These types of systems can also be split systems or package units and nearly all share a similar heat pump sequence of operation. A description of the various types of systems and how they work is below in this article on heat pump types. These systems utilize similar heat pump components but differ in how the heat pump works.

Heat Pump Types - From Geothermal Heat Pumps to Air Source Heat Pump Systems - Heat Pump Heating

A heat pump is a large refrigerator that moves heat from one place to another. When the temperature is hot and it is in air conditioning mode it moves the heat from the inside to the outside. When the temperature is cold it absorbs heat from the outside and moves it to the inside. Yes, there is heat in the air which is 40° Fahrenheit and the heat pump absorbs this heat and moves it where it can be used for comfort.

All air conditioners and heat pumps utilize the process of refrigeration to move heat from one place to another. The classic definition of refrigeration is a mechanical process that moves heat from a place where it is not wanted or needed to a place where it doesn’t matter. An air conditioner moves heat in one direction, from the inside to the outside, while a heat pump moves heat in both directions depending on the heat pump thermostat setting.

Geothermal Heat Pump Types How it works

Air Source Heat Pump Tips | Dual Fuel Heating

A dual fuel heat pump is a heat pump with a gas furnace for backup heating rather than electric heat strips.

Air source heat pumps have a backup heating source. In most installations, the backup heating source is electric heat strips. Electric heat strips are very cheap to install in most cases. However, while electricity is generally regarded as 100% efficient, producing it is more costly than other heating methods. For a more efficient heat pump, consider a dual fuel heat pump, or a heat pump with a gas furnace for the backup heat source. It will be more costly to install, but your monthly bills will be reduced.

Geothermal Heat Pump Types | Heat Pump Types

Geothermal heat pumps utilize the natural heat of the earth to produce heat and there are different types of geothermal systems available. Depending on where you live, whether you are located in a Northern or the Southern region will depend on the temperature of the earth but the temperature of the earth is warmer than the air is outside in the wintertime and cooler than the air is outside in the summer. The geothermal system takes advantage of this stable temperature of the earth to exchange heat in both directions. Because of these stable temperatures, the geothermal system is much more efficient than an air-source system.

The difference is the installation cost between the two. A geothermal system can cost thousands of dollars more to install than an air source heat pump but the geothermal system is much cheaper to operate and will generally give you payback for the extra installation costs within five years. Geothermal systems also have a longer life expectancy than air source heat pumps. There are also some geothermal systems that provide hot water for domestic use so the advantages of having a geothermal system are greater than having an air source heat pump.

Geothermal Heat Pumps - Loops | Heat Pump Types

Types of Heat Pumps - Many geothermal systems use an open-loop well system for a geothermal heat pump system. There are two wells drilled. One well is used to dump the water from the condenser and the other well is a feeder well. The feeder well feeds the geothermal heat pump system. This system uses a pump to pump the water to the dump well and from the feeder well. Certain conditions must be met for this system to work properly and reliably. Check with your local geothermal HVAC contractor to see if this is the right system for you.

Horizontal closed-loop geothermal systems have piping buried in the ground. The depth is from 4 to 6 feet in depth in trenches. The trenches are dug somewhere near the home or business where the geothermal heat pump is installed. When the geothermal unit turns on, a pump is also turned on. This circulates the water through the piping buried under the ground. The heat exchange process takes place between the piping and the ground where the pipes are buried.

Vertical Closed Loop | Heat Pump Types

Geothermal Heat Pump TypesTypes of Heat Pumps - The vertical closed-loop geothermal system is used for areas where land is limited like in a big city for a building or home that has a little plot. Holes are drilled into the earth more than 100 feet. The depth depends on the size of the system and how deep the holes need to be for proper heat exchange.

The piping is fed into the holes. The pipes are connected at the bottom with a U-bend. This also happens with the horizontal geothermal system. When the geothermal unit kicks on a pump also turns on. It pumps water through the piping in the earth for heat exchange. The difference is that piping is horizontally installed. Horizontal installation requires more land but less depth of pipe installation.

The closed-loop pond or lake system utilizes a pond or lake which meets certain criteria. The criteria are specific for use in a geothermal loop system. Obviously, the piping must be installed deep enough in the lake or pond to prevent freezing of the pipes. This system is cheaper to install than other methods for geothermal systems described. However, it is important that the pond or lake meet the criteria for geothermal heat pump use.

Check with your local geothermal HVAC contractor to see if the lake or pond meets the criteria. You must also consider local codes and regulations. Furthermore, the geothermal HVAC contractor will be knowledgeable about all these regulations.

Commercial Geothermal Systems - Water Towers | Heat Pump Types

Some commercial systems use a geothermal heat pump but instead of using the earth, they use a water tower. The water tower removes heat in the summer and a boiler to heat the water for winter use. Depending on how the system is controlled will depend on the energy savings realized from this type of system. Typically the water temperature is maintained between 70 and 80 degrees. These temperatures are maintained using the water tower or the boiler depending on the season.

Air Source Heat Pumps | Heat Pump Types

Types of Heat Pumps - Air source heat pumps rely on the temperature of the air outside for proper heat exchange. Since the temperature of the air outside can vary greatly these systems are less efficient than geothermal heat pumps. Air source heat pump systems also need a defrost cycle and backup heat. The reason is when the temperature outside falls below 38 degrees Fahrenheit the system loses its ability to absorb heat.

In this case, backup heat is needed. The majority of air source heat pumps utilize electric heating for backup heating. Other air source heat pump systems utilize gas or oil for backup heating.

The gas or oil backup heating systems are more efficient than the electric backup heating but the installation costs are higher. Furthermore, air-source systems are available in a package unit or in a split system.

A split system is where the air handler is inside and the condenser is outside. A package unit is where all the components are in one package.

List of Heat Pumps

A specific list will include all of the following heat pump types:

  • Geothermal Systems as described above
  • Air Source Systems which will include the following
  • Split System Heat Pumps where the condenser is remote to the air handling unit
  • Package Unit heat pumps where the air handler and the condenser are integral
  • Mini-split Ductless Systems
  • Portable Terminal Heat Pumps are the systems one would see in a hotel room
  • Window unit heat pumps

High Performance HVAC

Heat Pump Types