Heat Pump Chiller​

What Is a Heat Pump Chiller?

A heat pump chiller is a specialized HVAC system that provides heating and cooling by sourcing heat from water, air, or other fluids and transferring it to a fluid, utilizing the same basic components as a traditional chiller but with heating control capabilities. These systems are increasingly used in large commercial applications due to their energy efficiency and versatility.

Components of a Heat Pump Chiller

Heat pump chillers incorporate the same basic components as standard chillers and air conditioners, but with one added piece — the ability to heat which is sometimes achieved with the use of a reversing valve. Here are the components of a heat pump chiller and their functions:

• Evaporator: A liquid refrigerant absorbs heat from the medium that needs cooling, such as water circulating through a building, or from the outdoor air. This process causes the refrigerant to boil and turn into a low-pressure gas.
• Compressor: This component increases the pressure and temperature of the refrigerant gas. Compressors can be centrifugal, screw, scroll, or reciprocating.
• Condenser: The hot, high-pressure refrigerant gas flows into the condenser. Here, the refrigerant releases heat into a fluid used for heating and the refrigerant condenses into a high-pressure liquid.
• Expansion valve: This controls the flow of refrigerant in the system, reducing the pressure and temperature of the refrigerant before it enters the evaporator.
• Reversing valve: The key component in some heat pump chillers the flow of refrigerant within the vapor compression cycle, allowing the equipment to switch the roles of the heat exchangers between heating and cooling modes.

How Does a Heat Pump Chiller Work?

Heat pump chillers transfer heat rather than generate it. They extract heat from air, water, or the ground to heat spaces.

• Cooling mode: The system absorbs heat from the building’s chilled water loop and releases it outside, functioning like a conventional chiller.
• Heating mode: The system extracts heat from the outside air (or another source) and transfers it to the building’s water loop, providing heat for space heating, domestic hot water, or process heating applications.

What Are the Advantages and Disadvantages of Heat Pump Chillers?

The pros outweigh the cons with heat pump chillers in most cases, but to ensure you choose the best system for your building and its location, talk to one of our experts in your area.

Advantages

• Energy efficiency: Heat pump chillers can recover and reuse waste heat when they are simultaneously cooling and heating, significantly improving overall system efficiency compared to separate boiler and chiller setups.
• Cost savings: Energy efficiency can lead to lower energy bills over time. They are generally less expensive to operate than traditional boiler systems.
• Versatility: They can both heat and cool fluid, eliminating the need for separate cooling and heating systems.
• Lower carbon emissions: Using electricity instead of fossil fuels, especially when paired with renewable energy sources, helps building owners meet sustainability goals and regulatory requirements.
• Flexible installation: Heat pump chillers can integrate with several types of airside equipment, including VAV systems, fan coils, air handlers, and other hydronic systems.

Disadvantages

• Initial costs: The upfront investment can be higher than traditional systems.
• Climate dependence: Efficiency can decrease in extremely cold climates. Alternative heat sources, like geothermal, may be needed.
• Complexity: Heat pump chillers require careful design and controls to optimize performance and avoid issues.

Resources for Heat Pump Chillers

• Comprehensive Heat Pump Chiller Systems
• Webinar: Rethinking Hydronic Systems to Enable Building Electrification
• How Thermal Energy Storage Can Be the Key for Cold Climate Heat Pumps
• Customer story: Customer Experience Center in La Crosse, WI
• Customer story: Heat Recovery System Makes Impact
• Customer story: Retrofit Creates Sustainable Building Model

To learn more about how our heat pump chiller systems can help your business save energy and long-term costs and improve its sustainability, contact your local Trane representative today.