This is part three of a three-part series on the problem of home decarbonization in the U.S. Continue reading with part one and part two.
I’ve spent years trying to figure out how to get one-way ACs off the market. A few states are just beginning to try to encourage heat pump adoption, but historically there have been very few significant efforts, and none that have delivered at the speed and scale needed.
Given the typical cycle for updating appliance standards, the industry is unlikely to mandate a “technology change” like adding a reversing valve until 2036 at the earliest. California tried banning gas in new builds in 40 cities; more than 20 states saw those restrictions and responded by banning the bans. State-by-state mandates are slow, risk backlash if the wrong state goes first, and create cross-border headaches — think about Kansas City, which straddles Kansas and Missouri.
And nationwide consumer rebates? The most useful Inflation Reduction Act program, the $2,000 heat pump incentive, was rolled back by the GOP’s One Big Beautiful Bill. That said, that program and the HEEHRA/HOMES programs combined were projected to increase heat pump adoption by just 2%.
Every path leads back to the same conclusion, even for me, a person typically pretty skeptical about policy interventions: National policy to convert AC production to heat pump production is the only way to put a decarbonization “end date” on the calendar.
Two bills have been written to do this. The HEATR Act, introduced by Sen. Amy Klobuchar in 2022, would have established a manufacturer tax credit: payments for the companies producing heat pumps instead of one-way ACs, with bonus credits for cold climate models and for manufacturers who stopped producing ACs entirely. It was proposed in time to hypothetically make it into the Inflation Reduction Act, but too late to gain traction.
There’s an even simpler approach, if we can only rally the legislative support. My colleagues and I drafted the COOLER Act for Sen. Martin Heinrich’s office in 2023: a very simple bill that would incentivize distributors to only carry two way ACs/heat pumps, by offering a tax break that would cover the cost difference. Sadly, the bill has yet to be introduced; there just hasn’t been the political appetite for it in a moment with a ton of other competing priorities.
Federal legislation incentivizing the swap to heat pumps would be a significant and inexpensive step forward. No one would be taking anyone’s furnace away. Rather, consumers that switch to a hybrid system (as many in the Midwest and Northeast would likely do) would have more choice: two heating fuels instead of one. Messaging this correctly is essential to prevent backlash.
We don’t have to guess whether these incentives would work. At least at the local level, we already have evidence that it does. Vancouver, Canada required two-way ACs at equipment replacement and for new builds starting in 2023. I expected the implementation to have some bumps, and it just hasn’t. Distributors welcomed the change because it simplified inventory. Contractors adapted quickly. The market followed without friction.
We will likely need more state- and utility-scale AC to heat pump programs to prove out the model. Colorado and Maryland are already well-positioned to pilot the approach — and if they do, they’d potentially generate invaluable data and feedback for wider adoption. But to put a true completion date on home decarbonization, a federal bill is required.
Solving measurement and system problems
One hurdle to making this work is highly technical: load calculations. This is the part where people’s eyes glaze over, but bear with me. This one issue blocks more heat pumps in cold climates than anything else.
Manual J, the industry standard tool for sizing HVAC equipment, routinely produces heating load estimates that are double what homes actually need. I see load calculations in the 60,000–80,000 BTU per hour range for homes where runtime data shows actual loads of 25,000–40,000 BTU per hour. The first number requires a furnace. The second is well within heat pump range.
We won’t decarbonize homes in cold climates at scale until this discrepancy is fixed.
Why the inaccuracy? Well, contractors are naturally conservative, because what they really don’t want is a callback on a very hot or very cold day saying the system won’t hold the desired temperature. The few that run load calculations during a replacement job consistently make conservative assumptions, which make it look like the house needs more heat to keep it warm on a cold day than it actually does.
Meanwhile, contractors seldom measure air leakage — which according to NREL accounts for 20%–50% of heat loss.. Instead they make conservative assumptions that further pad the calculations.
Furthermore, the formulas for Manual J, even if they’re followed to the letter, are already 20%–30% conservative. It’s not hard, given everyone’s propensity for caution, for systems to come out at double the size needed. And furnaces have much higher outputs than heat pumps, which means that overstated calculations force homes to continue relying on furnaces when a heat pump would be the right choice in many homes.
This is solvable, though. Lidar-based tools like Amply and ConduitTech have helped, but a lower-tech option is also needed: for instance, tying load calculations to air leakage measured with blower door tests or else the home’s past energy use. I built a simple tool for this. Meanwhile, in Canada, the Building Decarbonization Alliance is developing load sizing standards based on past energy use and equipment runtime for retrofits; the U.S. could borrow them.
Realistically though, the 80%–90% of home HVAC systems replaced in an emergency are not going to get load calculations run. That’s where hybrids come in: Encourage homeowners to change the one-way AC to a two-way AC, and keep using a furnace. For both contractors and homeowners, this is a much easier sell.
Meanwhile, stock thermostat programming is also holding hybrids back. Most thermostats shut off heat pumps below 40°F — leaving enormous savings on the table — and don’t allow utilities to signal a switch to furnace during grid stress. This is again due to conservatism; thermostat manufacturers don’t want callbacks, and utilities are only beginning to ask for hybrid based demand response programs. For heat-pump-only systems, many default to electric resistance backup far too early, which hammers southern grids and consumer bills.
These are all software fixes, not hardware. Thermostat manufacturers could solve the programming problem tomorrow, with an over-the-air update.
Finally, it’s important that installation is done right. The vast majority, more than 90%, of residential HVAC systems have significant, detectable faults according to a DOE study: oversizing, improper airflow, refrigerant charge issues, duct leakage.
This matters even more for heat pumps because they’re more sensitive to installation quality than furnaces. A poorly installed heat pump will underperform, cost more to run, and generate angry customers who poison the market. Field diagnostics tools like MeasureQuick, quality-focused business models, and training that emphasizes measurement over speed are all part of the answer.
Design programs for the long term
If your goal is to design programs for longevity, the cost per project needs to be low — which naturally pushes you toward midstream (distributor-level) or upstream (manufacturer-level) incentives, rather than downstream rebates.
The best upstream example: incentivizing manufacturers to stop making one-way ACs, which would quickly and likely permanently transform the market. The cost, as estimated by CLASP, would be roughly $10 billion. This could be done midstream at distributors as well, which is what the COOLER Act was designed to do.
Meanwhile, downstream incentives often add friction. I’ve watched for almost 20 years now, and I’ve rarely seen a downstream program that wasn’t somehow problematic. One major reason comes back to the nature of home HVAC purchases: If 85% of systems are installed in emergencies, downstream programs are structurally incapable of reaching the actual market.
Another key piece of making sure these programs are durable is how the technology is positioned to the general public. Positioning matters.
Effective frames for the benefits of heat pumps include emphasizing comfort, comparable costs, and the fact that one-way ACs are obsolete. Ineffective frames, meanwhile, tell potential customers that making the switch is better for the planet, will save them thousands per year (which is rarely the case), or is what the government wants.
One set positions electric options as smart, flexible, comfortable. The other triggers political resistance or sets false expectations — unlikely to encourage enduring enthusiasm about home decarbonization.
The path forward
None of this is rocket science. Make the right thing easy with a supply-side shift to two-way ACs. Lead with what customers value. Build contractor capability and confidence. Set honest expectations. Improve quality.
The technology works. The economics work. The supply chain is ready.
What’s missing, however, is the discipline to focus on mainstream strategy instead of optimizing our pitch to people who already agree with us. We can keep perfecting our message to early adopters while wondering why the market isn’t transforming. Or we can accept that finishing home decarbonization requires reaching people who don’t care about decarbonization — and building programs, policies, and businesses that work for them.
The second path is harder. It requires letting go of climate-first messaging that feels morally urgent. It requires accepting that hybrid systems are good enough for now, even if they don’t immediately zero out emissions completely. It requires trusting contractors — many of whom are politically conservative — to deliver the transformation. It’s a shift in how we’ve been doing things so far, but it’s the only path that actually gets the job done.
Nate Adams, also known as “the House Whisperer,” removed his first client gas meter in 2014 and in the years since has taught numerous HVAC contractors how to do the same. He is a longtime electrification advocate, and on the advisory board for ACHR News. He and his wife Rachel create electrified immersive vacation rentals near the New River Gorge National Park, and own 11 heat pumps personally. The opinions represented in this contributed article are solely those of the author, and do not reflect the views of Latitude Media or any of its staff.
