Air Source Heat Pumps
Air source heat pumps have grown immensely popular over the last ten years as they are able to heat and cool homes and other buildings quite efficiently. Air source heat pumps are used in nearly all parts of the US. Although many people understand how air conditioners and furnaces work, they are not too familiar with air source heat pumps.
What is an Air Source Heat Pump?
Air source heat pumps transfer heat inside a building from outside, or transfer heat outside. These pumps use refrigerant systems that have condensers and compressors to soak up heat at a given place, releasing it at another place. Air source heat pumps could be used as space coolers or heaters. They are usually known as “reverse-cycle air conditioners”.
It is quite simple to understand why they have risen in popularity. First, compared to other HVAC equipment air source heat pumps are more economical to install. Second, they offer immediate savings on your domestic heating bills, and most importantly, they offer both cooling and heating in a single system.
How do Air Source Heat Pumps work?
An air source heat pump utilizes the principle of heat transfer in order to cool and heat your home. This is achieved through the transfer of heat from outdoors to your house during the cold months through the refrigeration process. The refrigeration system of an air source heat pump consists of two coils made of copper tubes and a compressor. One tube is indoor and the other is outdoor; they are covered with aluminum fins to help heat transfer.
When the heat pump is in the heating mode, the refrigerants in the coils draw heat from air, evaporating into gas. Then the indoor coil releases heat that was extracted by the refrigerant and the gas condenses back to liquid. A heat exchanger transfers the heat to your home. After cooling off, the refrigerant repeats this process. There is also a reversing valve often found near the compressor that could alter the direction of refrigerant flow.
How does the Energy Efficiency of Air Source Heat Pumps compare to other Heating Options?
An air source heat pump has several benefits over other heating alternative such as gas furnaces. The most important benefit is their superior energy efficiency (do not confuse it with operational costs). A lot of air source heat pumps have SEER values ranging from 14 to more than 21. Most air source pumps use electricity for transferring heat from one place to another. This means they do not need to generate heat on their own. The system simply and efficiently moves already-existing heat from one place to another.
Moreover air source heat pumps are more environmentally friendly as they do not need any fossil fuels in order to heat the home. Efficient air source heat pumps could lower heating costs if they replace or supplement a propane, electric resistant, or oil-based heating system. Actually, these pumps could heat your building or home for almost half the cost of conventional electric heating.
Air source heat pumps offer the following benefits:
- Reduce utility bills by switching from propane, electric resistance or oil to heat pumps
- As no combustion is involved they produce no carbon monoxide and are environmentally friendly
- There is no need to store fuel which is a real convenience
- You will not have to worry about running out of fuel
The amount of heat that air source heat pumps transfer inside your house will depend mainly on outdoor temperatures which can be a serious drawback. With the drop in outdoor temperatures, the heat output of the heat pump declines considerably. The following image show the heat output of an air source heat pump in Btu/hr at three outdoor temperatures.
What is involved in Installing an Air Source Heat Pump?
Although most air source heating pumps do not have complicated installation instructions compared to, for example, geothermal or ground heat pumps, it does not necessarily mean you should undertake all the installation tasks on your own. You should hire an expert in order to install the air source heat pump. This will ensure your heat pump runs as efficiently as possible.
Physical Set Up
As one of the most widely used models of air-source heat pump is the split version, we will cover that. A split-type air source heat pump has two units. One unit is installed outside your home, while the other is installed inside. Copper tubing is used to connect these two units. You will need to put refrigerant in the copper tubes as it will allow the heat pump to produce cooling for your house.
Moreover, the fan box will have to be installed outdoors in a safe place with power sockets. The fan box will be placed on a concrete slab.
Duct Work System
An air source heat pump provides both cooling and heating via a duct work system. Keep in mind however, that your home may not have any existing duct work system. Make sure you clarify this with your HVAC contractor prior to starting any work. This is because the price can escalate in case you have an inadequate or no duck work system at all. However, the good news is that the latest models of many air source heat pumps often do not need ducting in order to distribute cooling or heating.
Keep in mind that the electrical panel in your house will need to be reconfigured so that it can adequately accommodate the power requirements of your new air source heat pump. Keep in mind that the minimum demand is around 200 amps.
Want to learn more about Air Source Heat Pumps?
If you would like to learn more about air source heat pumps, contact Walker ClimateCare, and one of our team would be happy to consult with you to determine if it is a good fit for your home.