First, I tend to react badly to the usual SCV "We are going to disrupt <XYZ>" when there's nothing wrong with <XYZ>.
The current policy-driven push for heat pump systems is, at best, nonsensical.
Why?
Just speaking of the US (and guessing it might be the same in other regions) the power grid and power generation capacity are already stressed to the point where, in places like CA, power outages and having the governor ask electric vehicle owners not to charge their cars are a thing.
Now we want to push 80 million homes to ADD, not remove, electrical demand to the tune of kilowatts per home, in the name of efficiency?
This is deeply misguided. We need to get serious about upgrading our power generation and distribution systems before adding non-trivial demand.
Current estimates are that we need to double our power generation and transmission capacity to be able to support electric cars. Going with an electric heat-pump based system for cooling and heating means having the potential to add somewhere in the range of 3 kW to 6 kW or more of nearly steady-state load for 6 to 12 hours to tens of millions of homes.
While it is never a good idea to apply averages to this kind of analysis, if I were to do the math for the endpoints, we are talking about 240 GW to 480 GW of new power demand for 80 million homes going electric. That is nothing even close to trivial.
For context, a nuclear power plant is typically rated at 1 GW. This means we might need somewhere between 240 and 480 new nuclear power plants to support full electrification of our heating and cooling systems. And we are not even talking about large commercial buildings, hotels, etc.
Add that to the 1200 GW deficit for full electrification of ground transportation and we quickly approach a requirement for over 1500 new 1GW nuclear power plants.
No. You cannot do this with solar. You cannot do this with solar and wind combined. These technologies are not reliable. Under the best of conditions they might be able to reach 80% reliability. Another way to say it is that towns and cities will go dark 20% of the time without having 100% backup systems.
In other words, the energy story on this (not the startup, but rather the idea of placing all of our eggs on the magical electric-power-will-save-the-world basket) isn't good at all.
As far as the startup itself. I know there are first adopters out there who might jump on something like this. I am a first adopter of many technologies. I have spent a thousand dollars on 3D printers that turned out to be crap. Not a big deal. When it comes to my home, no, sorry. Not going to happen.
First of all, your company is a YC funded startup with no manufacturing history or infrastructure whatsoever. Sorry, this isn't like making smart watches. What you are going to do is come-up with a design, go to a company in China and make something. A unicorn. Your design will change based on what that company already makes. It will be, for the most part, not much different internally than what Carrier and other companies make.
The difference is that companies like Carrier have been around forever. They can stand behind their product and I can be assured they --and the extended support infrastructure that knows their product-- will be around for decades. You are one bank failure or investor decision away from being out of business.
Others may think differently, of course. In my case, there is no way I am going to spend tens of thousands of dollars on a unicorn that nobody will want to touch of maintain. I saw a post from someone in France who cannot get their heat-pump system serviced. That's a reality in the US if one installs something your local service infrastructure has never seen or isn't interested in dealing with.
Another consideration: Installing a no-name system in a home can have negative consequences when it comes time to sell it.
HEPA, air quality, smart thermostat, API's, cloud, etc. Yeah, no, not interested. As someone else said, a contact closure is all you need and want. No air conditioning maintenance guy is going to show up with a laptop to connect with your A/C unit via SSH.
Air filtering is easy and cheap. Depending on how you want to do it, it can, quite literally, cost less than $100 to have excellent filtering. I recently experimented with building a couple of these:
https://en.wikipedia.org/wiki/Corsi%E2%80%93Rosenthal_Box
I used 20 x 30 inch tall filters, which don't cost much more than 20 x 20's. The result was super-cheap high-performance filtration with measurable results and very low power consumption.
I do wish you the best. I am not a potential customer. In fact, I am surprised YC funded you. My guess is they are jumping on top of the billions that will be available in this segment. The investors will do well. I don't see anything in your product and company history to lead me to believe you will be able to produce anything "disruptive" at scale. The Carrier's of this world will get the bulk of that business, and rightly so.
Here's something you could do that would be disruptive. It has nothing to do with heat pumps but could easily be integrated into one:
Rather than build a single large system (say, 5 ton cooling capacity equivalent), create a single high efficiency "box" that effectively houses multiple smaller systems. For sake of a discussion, imagine a system that is five 1 ton units in one box.
Why?
Everyone wants zone controls. If you own a two level home, and you don't have a zone system, you hate your life. Upstairs is always ridiculously hot when heating and downstairs is freezing when cooling.
Come-up with a truly innovative way to create a zone system with room-scale granularity. Make it super easy to install without having to have ugly heat exchangers mounted on the wall. Easy enough that, when done, the home will not look materially different.
Do this and you will --if they trust you-- have lots of customers. Or, more likely than that, one of the large HVAC companies will acquire your company for the technology.
That's the real energy efficiency story. Room-scale granularity in HVAC at a price not materially different from a centralized single-zone system. I want thermostats (or sensors) in every room. There is no need to cool or heat the bathroom all day. There is no need to cool or heat the bedrooms when nobody is in there until the end of the day. A lot of homes would be just fine if one room was actively cooled/heated while the rest of the rooms were "off" and a couple (kitchen and one bathroom) were programmed to be at the JNC threshold (Just Nominally Comfortable --my term).
That, to me, would be innovative and disruptive. Not an easy task. You would have to come up with a way to build such a system in such a way that you did not have to penetrate the home with a million refrigerant hoses (a pair per room?) and work with the standard installation to the extent possible.
There's a lot more to something like this. Just making a heat pump that looks good and has wiz-bang controls, from my perspective, isn't disruptive at all. There are lower cost solutions in the market today that can be financed, people trust, contractors can install and support.
Your opportunity for disruption, in my opinion, is in delivering a material and non-trivial improvement to best-in-class performance of products available today. That, to me, means a granular zone system.
Personal context: I have decades of thermal management and clean-room design and operation experience as well as life-support level experience in aerospace applications. Some of the technology we helped engineer orbits the planet and, in time, will go to the moon.