Some jurisdictions in North America have already taken this step, she noted. The Canadian city of Vancouver has required heat pumps for all new air-conditioning systems since the start of 2023. The town of Aspen, Colorado has set similar mandates, although they don’t force homeowners to replace gas furnaces already in place, Tiffany noted. And the city of Denver will make the replacement of space and water heating at the end of its useful life with all-electric equipment mandatory by 2027, not only to provide more efficient and lower-carbon heating but also to improve indoor air quality.
The U.S. Environmental Protection Agency took a big step on this front earlier this year with a proposal to phase out Energy Star certification for stand-alone central air conditioners and furnaces and reserve the high-efficiency ranking for bidirectional heat pumps.
The EPA cited research from the Collaborative Labeling and Appliance Standards Program (CLASP), an international nonprofit organization, that found that if every U.S. homeowner replaced their central ACs with heat pumps over the course of this decade, home-heating-related emissions would decline by about 11 percent annually by 2032, while homeowners would save a collective $27 billion on energy bills.
The American Gas Association trade group decried EPA’s proposal as restricting consumer choice to more expensive heat pump systems. But environmental groups praised the move for giving consumers, contractors and efficiency-incentive program administrators a clear guidepost for picking products that “increase efficiency, lower utility bills, reduce air pollution and improve health, reduce global warming pollution, and deliver better performance.”
Getting consumers — and the HVAC industry — on board
Nate Adams, CEO of HVAC 2.0, co-authored a study in 2021 that informed the CLASP analysis that EPA cited in its proposal to change its Energy Star rankings. He’s definitely an advocate of replacing central AC systems with heat pumps.
Still, Adams warned that EPA’s proposed change to Energy Star won’t necessarily drive a huge change in how U.S. homeowners and contractors do business. That’s because Energy Star only applies to the highest-efficiency and highest-cost products, which make up roughly 15 percent of all HVAC sales, he pointed out.
Still, “I view this as a change in the winds” of government policy on home heating, he said. “Now there’s been a finger put on the scale for heat pumps.”
Replacing central AC systems with heat pumps is also a relatively straightforward change for HVAC manufacturers, according to Adams. While companies that make furnaces may oppose regulations that restrict their future market, many of the world’s leading HVAC equipment manufacturers make both AC systems and heat pumps, he noted. Distributors of home HVAC equipment are likely to support policies that reduce the scope of products they have to carry to meet market demand, he added.
It’s less clear how eager HVAC contractors will be to make the switch from central ACs to bidirectional heat pumps, however. Adding new mandates on what equipment can be installed “messes with the sales process, because it brings equipment selection and pricing to the beginning of the process, instead of the end, which is hard,” he said.
Properly selecting the right heat pump to both heat and cool homes in colder climates is also tricky, Adams said. Heating loads are typically larger than cooling loads in those circumstances. That means homeowners who want to replace their AC with a heat pump might have to choose between a system that’s oversized for their cooling needs to cover their heating needs, which will drive up costs, or pick a smaller, cooling-load-optimized heat pump and rely on alternative heating sources for the coldest parts of the winter — what’s called a “hybrid heating” approach.
Most Californians have relatively balanced heating and cooling loads, making them good targets for bidirectional heat pumps, Borgeson said. But homes in colder parts of the state may want to leave their furnace in place so they can turn it on when temperatures drop. They’ll still burn far less fossil fuel using that approach, as long as thermostats to control those dual systems are properly installed.
Advances in heat-pump technology over the past two decades have made them capable of keeping homes warm in subfreezing temperatures, Tiffany noted. But still, allowing homeowners to keep their furnaces helps defuse the risk of pushback from consumers worried that their choices about how to stay warm in wintertime are being limited by regulations on what kind of equipment they can install to keep cool in summertime, he said.
Adams agreed that customer choice is a must for a successful policy. “We need to get to 100 percent heat-pump installations by 2030,” he said. At the same time, “you have to make this about having two choices for home heating, rather than one.”
To be sure, this hybrid-heating approach will eventually run up against future bans on selling and installing new fossil-fueled heating systems. But broader policy support for installing heat pumps to replace AC systems should build HVAC industry capacity for getting these cold-weather heat pumps into customers’ homes, apartments and businesses in far greater volumes.
“We really want to make sure you’re planning for a heat pump if something dies — whether it’s your air conditioner or your furnace,” he said.
