Heat Pump Water Heater Guide

Best Practices and Technical Considerations for Single-Family New Construction

This web guide covers the basics of integrated Heat Pump Water Heaters, including design, installation, and maintenance. It highlights best practices and common technical considerations for professionals supporting Heat Pump Water Heaters for single-family and multifamily new construction.

Please note that the term "Heat Pump Water Heaters" used through most of this web guide refers to integrated Heat Pump Water Heaters, except where stated otherwise. The web guide is current as of June 2024; a PDF version is available at ENERGY STAR Heat Pump Water Heater Technical Guide (PDF, 721.69 KB). 

Introduction

Heat pump water heaters are a key advanced electric technology that will help build our clean energy future. Heat Pump Water Heaters extract heat from the surrounding environment and transfer it into the water inside the tank. They are electrically powered and deliver hot water up to five times more efficiently than standard electric resistance, gas, and propane water heaters. 

The most commonly used heat pump technology for domestic water heating are integrated Heat Pump Water Heaters.* Integrated Heat Pump Water Heaters have their heat pump compressor and heat exchangers attached directly to the water heater’s storage tank. They typically harvest heat directly from the surrounding air, but can also draw from air supplied through ducted vents. Most models also have electric resistance heating elements—like traditional electric water heaters—to use as a backup when needed, which is why Heat Pump Water Heaters are sometimes called Hybrid Water Heaters. 

*Other heat pump technologies that can support domestic hot water production include split system Heat Pump Water Heaters, air-to-water heat pumps (AWHPs) designed principally to provide space-conditioning, ground source heat pumps (GSHPs, also known as geothermal heat pumps), GSHPs with desuperheaters, and gas heat pump water heaters (GHPWH). These technologies may be suited for some applications, but are not discussed in this guide.

Benefits of Heat Pump Water Heaters

Benefits to Homeowners

• Reduce operating costs. 

Residents will enjoy significantly reduced operating costs compared to standard electric water heaters or oil, propane, or kerosene water heaters. ENERGY STAR certified Heat Pump Water Heaters use 70% less energy than a standard electric water heater, which could save a household of four approximately $550 per year on its electric bills and more than $5,600 over the unit’s lifetime. There can also be operating cost savings relative to natural gas, but these depend on local utility rate structures. 

• Offer more control options. 

Heat Pump Water Heaters may offer flexibility with a digital control panel or remote management application to control temperature setpoints and adjust operational modes, maximizing efficiency. Most also provide grid connectivity and interoperability options for participating in demand response programs, and may allow the user or installer to enter a utility time-of-use rate plan to maximize cost savings. Heat Pump Water Heaters may also provide more capabilities to track performance through energy consumption and operational status reporting.

• Improve indoor air quality and safety. 

Heat Pump Water Heaters do not create toxic combustion exhaust gases, such as carbon monoxide. By eliminating this combustion appliance, Heat Pump Water Heaters also eliminate the risk of fire or explosion that can be caused by a fuel-fired water heater or associated gas piping.

• Reduce residents’ carbon footprint. 

Heat Pump Water Heaters run on electricity. Due to their high efficiency, this reduces the carbon impact of domestic hot water use, even in locations with carbon-intensive grid electricity. The emissions savings are even greater in locations with cleaner, low-carbon grids.  

• Represent a smart consumer choice. 

With available local financial incentives and federal tax credits for qualified products, along with typical 10-year manufacturer warranties, Heat Pump Water Heaters can be a cost-effective long-term product option.

Benefits to Builders and Installers

• Create new business opportunities and jobs for installers. 

Installers can be market leaders and help their customers take advantage of utility, local, state, and federal incentives for installing ENERGY STAR certified Heat Pump Water Heaters, and also help builders meet advancing energy codes.

• Increase marketability. 

Some homeowners are concerned about home energy independence and reducing greenhouse gas emissions. Heat Pump Water Heaters help address those concerns while providing access to special incentives, rates, tax credits, and smart connectivity information and controls, where available. Builders that install Heat Pump Water Heaters can sell these benefits as part of a “smart home of the future.” In some markets, Heat Pump Water Heaters with communicating modules can allow the homeowner to take advantage of demand response programs or time of use electricity rates for additional benefits.

• Speed construction and design. 

By avoiding gas service installation, contractors can eliminate construction delays caused by waiting for gas line easement approvals and avoid making accommodations to locate gas meters in construction plans that must meet difficult clearance requirements.

Heat Pump Water Heaters in ENERGY STAR NextGen Certified Homes

While this guide is applicable to all residential new construction, it is primarily a resource for builders participating in the EPA’s ENERGY STAR NextGen™ Certified Homes and Apartments program, which requires the installation of ENERGY STAR certified Heat Pump Water Heaters.