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I’m curious what’s the rank sort of items a typical apartment dweller would want to keep on backup - for me it would be WiFi router, phone charger, microwave, kettle and a couple kitchen lights. Any power restrictions that would preclude running microwave or kettle?

Very cool. You mention powering connected devices - is it feasible to push power back through the outlet to power parts of the home? Euro solar panels are doing this I believe.

You're right, heat pumps have been around for a while, but they're only at 15% market share across the whole US. The Southeast, for a few different reasons, has the highest market share. (1) It doesn't get that cold, and magnitude of heating/cooling loads are close enough that single stage equipment provides an OK experience. (2) There's very little natural gas infrastructure.

Cold weather heat pumps have recently become popular and enable increased adoption in the northeast, and the fact they're so efficient means they're competitive even in areas with a lot of natural gas infrastructure.

The Electric Air system can provide a lot of dehumidification. For your specific situation dedicated dehumidifiers are probably the right solution, unless you need a fair amount of cooling in addition to the dehumidification. This is because for purely dehumidification you need some reheat after chilling the air to condenser water out. With a dedicated dehumidifier you get this for free from the condenser on the other side of your refrigeration cycle. In the Electric Air system the backup strip heaters provide the reheat in the air handler, but using them a lot is expensive.

My main worry for you would be clearance in front of the condenser. These are side discharging units and require 4ft clearance in front for the air exhaust stream. Rough foot print of the condenser - 36" x 15".

Very cool prototype. Fresh air is a bigger deal than people realize. Shoot me a note at the email in my bio, I'd love to connect.

You're right - hardware is tough, and the scope is large. But this is an important area to build better products, there are a lot of people passionate about this/want to work on this and the hardware doesn't have to be designed from scratch. As for trust, the deposit is pretty low stakes, $100, fully refundable, reserves your place in line for a system. For those of you that placed a deposit, thank you, it means a lot!

More than 2M per year - this article implies 8M combined natural gas and heat pump installs in US: https://www.canarymedia.com/articles/heat-pumps/chart-americ...

What's your preferred thermostat?

Yeah, its a good question. I think 'direct to homeowners' has generated some confusion that this is a DIY product. After a purchase we have one of our contractor partners perform the install, they also bring the unit with them, we don't ship the unit to you and expect you to find your own installer or DIY.

In the future we'll likely show the condenser more in context, a backyard or something similar.

I don't know that much about thermoacoustic heat pumps. I do suspect they're less efficient than a standard vapor compression heat pumps, otherwise that would be their main selling point in the commercialization project underway: https://www.blueheartenergy.com/ourtechnology.

Heat pump water heaters are great, also a much simpler install than an HVAC system.

Only 17% of homes have heat pumps at the moment. 80M (though I believe its closer to 88M) homes in the US are single family detached homes.

What region are you in? Local contractor knowledge around heat pumps is quite regional.

It can be very regional, most of my specific discussions have been in the Northeast and the SF Bay Area. What area did you do this in?

Thanks!

Its an interesting idea. Install would be more expensive because you have to fit it nicely into the ceiling drywall and also snake refrigerant lines through the ceiling. Wall units typically have a hole drilled straight through the wall for condensate tubing and refrigerant line access. There's a wall unit on the Electric Air preorder site, thoughts on the aesthetics of that?

Not a dumb question, you've hit on one of the best features of these systems. They act as a heater in the winter and as AC in the summer. Same system.

Thanks for your perspective. What do you think is needed to move the needle on heat pump adoption/ make them a more compelling product?

The size ratings are confusing. This is really a ~19kbtu unit at 5F. Most homeowners do not want a DIY solution, they want it professionally installed. And this system lacks air quality features (HEPA, fresh air intake, humidifier) and the thermostat.

> By going direct to the homeowner you are targeting the venn diagram union of "people who are willing & able to do the work themselves"

This is meant to be installed by a professional contractor, not the homeowner.

> How are you going to build your service network?

Compensate the contractors fairly and act as lead gen.

> Who are the decision makers in your target market exactly?

Homeowners. Not targeting multiunit residential or new builds, they care less about efficiency because they don't bear the cost of ownership.

> What? How could duct work possibly be incompatible with a heat pump?

A natural gas furnace requires ~150cfm airflow per 10kbtu heat produced, while a heat pump requires 330cfm per 10kbtu. This large mismatch in required airflow means that if you replace a natural gas furnace with a like sized heat pump, you've likely exceeded the ability of the air handler blower. Luckily most natural gas furnaces are grossly oversized for homes. The way you find the right size unit is with our software.

Indoor or outdoor coil, copper tube-and-fin or aluminum microchannel?

Thermostat operates as a standalone device, no internet connectivity required. If you connect it to wifi it receives demand response, weather and TOU signals to reduce your utility bill.

We could be more clear on that claim. Temp variation within a room - ducted variable speed equipment solves this well. Temp variation between rooms - either need zoned dampers, programmable vents like Flair, or ductless units controlling each zone.

Thank you for pointing that out - just fixed it!

Yeah, definitely aware of this tech, and its often found in commercial applications. Probably overkill for residential stuff though, HEPA is already very good.

Up to homeowners to decide how much energy optimization they want. You can easily enable/disable DR as a homeowner.

Haven't looked at that. Dictating compressor design requires some massive scale as a business, or taking on the design and manufacture yourself, which I wouldn't recommend to startups. Also, I suspect that increased vapor injection ports has diminishing returns (but I haven't done the calcs on it).

Yep, definitely possible and done in this system. Depending on the details of your house + climate you will be limited on how high on humidity you can go in the winter. This is to prevent condensation in the structure.

Yep, this should be possible.

Not at the moment, working on a tool like this for the preorder site! There are btu/sq.ft. rules of thumbs that are not appropriate for heat pumps (you can easily oversize by 100%).