How Does a Heat Pump Work?

Adaptable to almost every application, heat pumps are rapidly becoming popular in homes and businesses. A heat pump has a mechanism that allows it to extract heat from one point and transfer it to another. For most homeowners, it’s the energy-saving ability that makes it so attractive.

These devices use less energy in transferring heat from one location to another. You can use a heat pump to pull heat out of the ground to heat your office building or home. Additionally, you can use them to cool a building as well. Read on to learn more about how heat pumps work.

The Refrigeration Cycle

When it comes to cooling, refrigerators and heat pumps work in a similar way. The heat from the inside is extracted and moved outside the space. Through a three-step process, heat pumps convert liquid refrigerant into a gas. It then converts it back into a liquid. This is the conversion phase, or in layman’s language, the refrigeration cycle.

A heat pump has three main components: the compressor, condenser and evaporator. Each plays a crucial role in the conversion phase.

Step one: The compressor is located in the outdoor unit of the heat pump. It uses pressure to heat the cool refrigerant gas before pumping the high-pressure gas into the condenser.

Step two: After receiving the hot gas, the condenser cools the gas into a liquid using a fan. This happens as the gas squeezes through coiled metal loops. The released heat then escapes through the metal fins located on the condenser’s exterior into the outside air.

Step three: The cooled liquid finds its way into the evaporator through the narrow valve. This way, the refrigerant flow slows down. As the liquid passes through the unit’s cooling coils, it evaporates, removing heat from the living space.

Types of Heat Pumps

Since heat pumps are equipped with the reverse operation, you can use them for heating as well as cooling. Some models can even increase your hot water supply. Generally, how heat pumps work depends on the type of installation you choose.

1. Air-Source Heat Pumps

The air-source heat pump is one of the most used types of heat pumps. It transfers the warm indoor air outside and then pumps it inside. As the air enters, it passes through the refrigerant-filled coils.

The air-source heat pump is pretty basic. It has a compressor, reversing valve, two fans, and refrigerant coils to make it work. Here’s an overview of how this type of heat pump works.

This unit is commonly known as the air-air heat pump since it transfers the hot outdoor air to your indoor air duct. When you modify them correctly, you can effectively use the air-source alongside your other heating systems.

The reversing valve is behind the cooling effect of the air-air heat pump. By reversing the refrigerant flow, it makes the system function in the opposite direction. Instead of producing heat, the air-source heat pump releases it as compared to your AC.

During the reverse process, the refrigerant absorbs the indoor heat and transfers the heat outside. It’s at this point that the heat is released. This allows the refrigerant to cool down and drift back to pick up more heat. The process repeats itself, thus keeping you nice and cool.

By now, you know that air-air heat pumps use the outdoor fan to flow air through refrigerant-filled coils. These coils transfer the hot air indoors, where a second fan blows it away from the coils. The cool air is then distributed through your home.

Some air-source heat pumps have a single packaged unit that contains both sets of coils in a single box. Depending on the model of your system, you’ll need either one or more components to distribute heat.

Absorption Heat Pump

Now, let’s consider the absorption heat pump. This is an air-source pump that’s powered by geothermal-heated water, propane, natural gas or solar power rather than using electricity.

You can use this type of heat pump for large-scale applications. However, they’re mostly available for homes. There’s only one significant difference between the absorption pump and the air-source heat pump.

Rather than compressing the refrigerant, this type of heat pump absorbs ammonia into the water, which is then pressurized by a low-power pump. The heat source then boils out the ammonia, and the process begins all over again.

When looking for an absorption pump, it helps to know their ratings. Manufacturers rate these appliances using a coefficient of performance (COP) measurement. You’ll need to look for a COP above 0.7 for cooling and above 1.2 for heating.

Other Kinds of Heat Pumps

1. Mini-Split Heat Pump

Does your home have an air duct to distribute heat? If not, don’t fear. You can use a one-of-a-kind type of heat pump known as the mini-split heat pump. It connects the outdoor air-source unit to various indoor units.

These indoor units then connect to space or water heaters. Since the mini-split systems have flexible locations, you can effectively use them for retrofitting your home with a heat pump system.

Another plus is that while installing it, you only need a 3-inch conduit coming through the wall. Mini-split heat pumps are also versatile. You can install the indoor air handlers in ceilings, walls and on the floor.

2. Reverse Cycle Chiller (RCC) Heat Pump

Rather than heating and cooling air, the RCC heat pump heats and cools water. You can also operate them effectively in temperatures below the freezing point. In a Reverse Cycle Chiller, the pump links to an insulated water tank which it either cools or heat.

Then, the system pumps the cooled or heated air away from the tank passing through the ductwork to either one or more heating zones. You can also use the RCC to pump hot water through your radiant floor heating system. This helps keep you comfy and warm throughout the cold winter season.

3. Cold Climate Heat Pump

The cold climate heat pump is one type of pump that you use even at the lowest temperatures. This heat pump can detect the minimum amount of energy required to offer the desired temperatures then adjust accordingly. This way, it never wastes energy.

Rely On the Experts

Now that you know how different types of heat pumps work, there’s only one step left: installing your system. Proper installation is vital for long-lasting services from your new heat pump system. At Hoff Heating & AC, we have over three decades of experience, so you can always rest assured that we’ll get the job done right the first time.

Our licensed and NATE-certified technicians will inspect, repair and maintain your home’s heat pump of all makes and models. We’re a Lennox Premier Dealer that offers regular maintenance services to maximize performance and efficiency. You can rely on us for all your heating needs in O’Fallon and the surrounding areas. Contact Hoff Heating & AC today for more information about heat pumps or to schedule one of our comprehensive services. We can also provide a full range of cooling services as well as geothermal consults.