A heat pump is said to be the most energy efficient HVAC option on the market. How is this possible? How the heat pump provides heating and air conditioning is crafty. Rather than creating heat, the heat pump either uses air or water to create temperature control in the house. Additionally, rather than buy a giant central HVAC unit or a separate heating and air system, a heat pump is a two for one deal. Both heating and cooling is with this system. That means only one system to get HVAC repairs, service and tune ups on. Some homes have to call an HVAC business a couple times a year. One service call might be to have the furnace checked out and then the other service date will be at a different time of year for only the cooling system. Anytime the HVAC contractor comes into a home with a heat pump, both heating and air functions are being cleaned, oiled and inspected. Less service required and the HVAC system becomes more efficient as it is maintained. There are many different types of heat pump systems to choose from. The homeowners choice depends on if they want the air or water used to create climate control, how much they are willing to spend and how much upheaval are they willing to have. Typically there is a geothermal heat pump that can be an air or ground source type.
Geothermal heat pumps contain an indoor air handler and outdoor compressor for the device to work. The outdoor unit connecting with this system is buried underground to utilize that temperature. Think about the summertime and how hot the air is. Using an air source heat pump would be very difficult to have cooling if the temperatures are around 90 degrees. Usually those types of heat pumps have the air run through refrigerant to create cooling. With a ground source geothermal heat pump, the piping is installed under the lawn where the temperatures are colder. Typically the temperatures should be close to 45 degrees in the summer if you have the device deep enough in the ground. What about with heating in the winter? Believe it or not, the temperature underneath the cold, ice and slush can be around 75 degrees because it is protected. A geothermal heat pump is able to utilize that heat and pump it to the indoor air handler. The home has quality heating without using oil or gas to create it. The method is a much more efficient one. When it comes to ground source geothermal heat pump systems, you really do have four options. There are closed loop systems that are horizontal, vertical or pond/lake. The open loop system is the last geothermal option.
The closed loop is typically plastic tubing buried in the ground or submerged in water. The heat exchangers transfers the heat between refrigerant and antifreeze solution in the closed loop. You can instead pump the refrigerant through copper tubing as well to create climate control. This method is typically with a horizontal or vertical loop system. What is the different besides the obvious? A horizontal system is usually the most cost effective for residential HVAC customers. The installation requires a trench around four feet deep, and uses two kinds of pipe. The piping can either be side by side in the ground or have opposite sides buried deeper. A vertical method is more for commercial needs. A giant business or a school uses a vertical system due to the land that the HVAC business has to work with. The land is often times restrictive rather than bountiful, so the vertical loop system works better. The soil also is too shallow for trenching and the landscape cannot be disturbed. So for a vertical loop system, holes around four inches are drilled in a 20 feet apart range around 100-400 feet deep. Two pipes go in the holes and are connected at the bottom to form a U shape. They are connected with horizontal piping placed in the trench and then linked to the building. The pond/lake option is the most cost effective but least typical. If there is a decent body of water supply, piping is placed underground into the water. It is coiled in circles around eight feet apart in order for the piping to not freeze with the water in the winter. Heat pumps also can be in a closed loop system or ductless as well. A closed loop would be used with a buried well or a surface body of water to work with the heat exchange. The fluid circulates through the system and the water returns to the ground well. If a home has an adequate and clean water supply, it is often used.
A heat pump system is made for temperatures that do not drop below 40 degrees though. If the air is too cold or the water, the heat pump is virtually worthless for heating. That is why hybrid heat pump models are out there. This combines a gas heating device with the heat pump. While the heat pump takes care of the cooling function, the gas method is tagged in to provide heat. The dual fuel system on its own is able to alternate from gas to electric based on the outdoor temperature. It is more effective to use a heat pump, so as long as the temperature permits it, the device is using electricity. Once the weather drops, it changes over to gas so the home never has to go without heating. Another style of heat pump that is a little different would be a ductless or mini split heat pump device. This device is used for homes that don’t have ductwork or that cannot take the installation of air ducts. The ductless system instead uses multiple indoor air handlers in the home each with a thermostat. Each of those devices connects with the outdoor one to work as a whole. Each room however can be its own individual temperature allowing for zone control. It is a fairly cost effective and simple HVAC installation process.