Interesting. I suspect that pure A/C is pretty much on the way out, even if a gas furnace is also installed in a home:
I have a duel fuel system. Heat pump and a propane furnace. I read recently that heat pumps are becoming better for heating below freezing temps. The problem before was the compressor units having exterior ice/frost buildup and the defrosting cycle taking too long to support the system. My heat pump doesn’t really produce well below 45 degrees. It’s an older unit (12 years) and needs to be replaced. That said, I went through $1800 in propane this year… 
because I used the furnace more… 
I guess we know how that “global warming” is treating you.
Out of 100 inspections in this area we might see 2 or 3 with a heat pump. 
WTF is this suppose to mean?
That aspect of heat pumps has REALLY changed: they are far far better at low temperatures. The physics are unfavorable at low temps – heat pumps are magic for moderate climes – but the low temps are way less of a challenge now for a modern unit.
Unfortunately many of the codes will push for all electric, where a mixed fuel approach can do a lot of good for wallets and longevity of systems.
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I have dual-fuel system in my home as well. I run the two-stage heat pump down to 20 degrees and then to a variable speed gas furnace.
There is the comfort set point and the economic set point for figuring out what temperature to switch over. Most people don’t like lukewarm air coming out of their registers, so they like a higher set point. The economic set point is typically much lower, but it is a bit more challenging as the price of gas/LP and electricity are ever changing.
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Here is the crux "“We all know that sustainability is a megatrend,” Carrier Global Chairman and CEO David Gitlin told a group of investors in February. “HVAC has to have a critical seat at the table.”
This is an article of buzz words to satiate the woke masses without any new developments. Most of the change will be pushed by regulation rather than economics or real technological advancements. Don’t hold your breath for any massive shift in the short term. Run the numbers before investing.
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I replaced my AC unit 5 years ago and expect it to last another 10. So, unless there is a premature failure of my condenser unit, I’ll be using my HE gas furnace to heat my house for the foreseeable future. If I had to buy one today though, I would without question go with a dual fuel system not only because of efficiency but also the advances in heat pump technology.
I saw more dual fuel systems last year than in my previous 20 years combined. They are becoming more and more popular in my area.
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Curious… How many years to go before you theoretically recoup your costs/expenses from the potential savings?
Out of 100 inspections in my area, I might see 10 furnaces with separate AC and 90 heat pumps.
The oldest and the newest builds in TV are all heat pumps. The furnace/AC systems were done from about 2005 to 2016.
It’s mostly working for me, but the signs of change are undeniable. It might not go well longer term.
Recoup my costs/expenses from what? My AC went out and I either had to replace it or live without it.
Now if you’re talking about my new vs my old AC, I was told the new condenser was considerably more efficient than my old one, but I don’t expect to get anywhere near the 4K back that I spent on it in savings, regardless, when it gets hot out it’s worth every penny and more. 
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Yes, that’s what I was leading up to.
I see posts and hear people talk about their big, new, fancy HVAC system that will supposedly save them boatloads of money.
For what some of these systems cost, and the way many people use them, I just can’t see many of them saving even 5 cents!!
I’m still running my 1991 Lennox Pulse furnace, and even older A/C unit that no longer has any visible data. I have the system serviced every two years, and keep up the maintenance myself.
I had to replace the Control Module about 10 years ago, but that’s about it. Sure, the A/C is a bit weak, but still works when I need it. That sukka isn’t getting replaced until it blows up!!
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