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Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

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Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#281

Post by nemo44x »

izolate wrote: post #152

I live in Buffalo NY, and from the recent record-breaking snowstorms, I've concluded that the push for electrification of home appliances may not be the best solution. Although gas furnaces still require electricity, they can operate for a more extended period on a generator, and gas stoves are a crucial backup option for staying warm during a power outage. Until our electricity grid becomes more reliable, I would he…

Also so many of our electric lines are above ground. I wouldn't feel comfortable 100% relying on that. Snow and ice take these things out in the winter and summer storms have their way too. And then the unreliable grid. How many brownouts have been occurring in part of the USA over the last few years?

I actually have a heatpump but I also have 2 furnaces/ACs as well for 3 systems total for my home. I don't plan on moving to electric for stovetop anytime soon.

Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#283

Post by cmui »

gwbas1c wrote: post #280

What's the COP? There's just a vague 3-5x more efficient claim on your web site. More efficient than what? I currently have a 5-year-old 2.8ish COP whole house system that won't last forever. I get a monster bill in January and February, so when it's time to replace it, I'd like to go with something a bit more modern.

Good questions. A heat pump is 3-5 more efficient than any fossil fuel furnace. Fossil fuel furnace is 70-96% efficient, heat pump is typically between 300-500% 'efficient'. COP varies depending on the outdoor conditions, but you can infer COP at various temperatures by looking at the HSPF2 (heating season performance factor) which is the weighted average of the btu output/watt input at various outdoor/indoor conditions.

Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#284

Post by simplyaccont »

heatpumpfan wrote: post #98
obituary_latte wrote: post #78

Does it explain somewhere that I missed how the different size units translate to sq. ft.? I would think that would be a great way to convey which size might work for people, but I might be missing some other factor that doesn't allow for that conversion?

Sizing heat pumps by the sq. ft. is hairy reasoning. Load calculations take into account climate zone, insulation, building materials, orientation, ceiling height, etc. Any recommendation based on 2D area is sketchy. For replacement of existing professionally installed systems, going by the capacity of the installed unit is a better shortcut.

There is actually good reason to bump up capacity by half a ton to ton, unless currently installed unit was sized recently. The reason for this it's that design temperatures jumped up, sometime in a big way in a recent ashray published design conditions (and many companies don't even know that this is the case and use those from 10 years ago or more). And even the published numbers tend to be off and they usually use one specific weather station in a region that may or may not have same weather as you.

When I replaced hvac a couple of years ago, I retained company to make manual j calcuation as none of hvac contractors were willing to do it. I provided it with design temperatures that I calculated after scrapping data from a bunch of private weather stations in few miles radius

Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#285

Post by jhallenworld »

I had a recent experience with replacing the main blower motor on my American Standard gas furnace: the variable speed motor has firmware, so can you guess what they did? The motor has to be programmed by the distributor or it will not work in your furnace. You have to provide the furnace's serial number for the programming. Worse, the local distributor would not sell it to me! They will only sell it to an installer. "Qualification" for an installer is load of nonsense- they just want your EPA refrigerant certification- which is nothing compared to a real license, like plumbers or electricians.

So please:

No serialized parts.

I should be able to buy replacement parts from you or common online suppliers without hassle- like amazon.com or supplyhouse.com.

I should be able to install it myself, at least in theory: so unit comes pre-charged, and various lengths of linesets are available so I don't have to do any brazing.

There is a company making a window unit heat pump: this one https://www.gradientcomfort.com/

You should make something like this.. basically a zero-installation work version of your product. This will be a big hit in places with insane labor costs- like New York City.

Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#286

Post by cmui »

hectormalot wrote: post #261

This is a really important consumer problem to solve. We retrofitted a heatpump into our home about a 18 months ago and it wasn’t a great experience. Ranging from contractors not even replying (retrofit being harder than new homes), wildly different quotes and setups, lack of (API) integration, uncharitable on planning and timelines, Etc. Note: This was before the energy prices spike because of the Russian invasion i…

Thanks for the feedback! I'll take a look at those two products.

Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#287

Post by briHass »

Would've loved to see a different approach to the typical refrigerant-split units. I'm EPA certified, and do my own heat pump work, but something that could really blow up the heat pump space would be a closed-loop refrigerant system that uses water lines to the indoor coil/air handler. This would make the system a true DIY self-install, since you'd never be messing with refrigerant loops.

The indoor coil/AH could be made as lightweight and small as possible (or multiple configurations) so it could easily be installed by a DIYer or a handyman for extremely low cost using insulated PEX lines for the water with basic tools. The outdoor unit would be heavy and require an electrical circuit, but would otherwise be as easy as swapping a window-unit AC.

Just like with solar, the biggest problem with adoption of heat pumps is labor cost to install. The units themselves are shockingly cheap (and continuously getting cheaper), but labor adds 3-4X the cost of the unit itself. The certification, tools, and knowledge to handle the refrigerant is the 'secret sauce' used by HVAC companies to keep prices high. Imagine how few people would have window AC units or refrigerators if they needed to be installed by an HVAC company that wanted to make $300/hr to install.

Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#288

Post by el_don_almighty »

Parts & Service documentation means more than software

The nerds can always reverse engineer practical controls. As a systems integrator, your job is providing access to comprehensive service information and long-term, easy access to parts. This is harder than it seems because of the necessary infrastructure and product management control. (Engineers are always tweaking something)

Of course, then you have to withstand the inevitable liability risk and lawsuits from idiots improperly installing capital goods in their homes. Let's be honest, there are people out there struggling to fasten their airplane lap belt...

The technology is NOT the hard part, it's all in the distribution and support

I would make sure your systems focus more on self-diagnostics, data logging, and anything else that makes troubleshooting faster and easier

Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#289

Post by kiddz »

Hey Chris. . . given the novel nature of your product (it looks very sleek btw) and you're looking to gather feedback, maybe we can talk using askhumans.io to gather feedback at scale? also, many years ago, I worked on compressed air energy storage on the demand side and we looked at co-generation opportunities to drive the caes turbines. anyways, would love to connect.

Re: Launch HN: Electric Air (YC W23) – Heat pump sold directly to homeowners

#290

Post by Ekaros »

londons_explore wrote: post #102
fauigerzigerk wrote: post #63

I keep reading lots of horror stories about heat pumps. People are complaining about all of the following: - Enormous energy bills because under some conditions (cold weather?) heat pumps use a lot more energy than expected. - Heat pump equipment and radiators taking too much space in small homes. - Cold homes and/or a requirement to keep windows shut because heat pumps just don't generate enough heat. - Only suitabl…

Heat pumps are trying to compete against very inefficient, yet very powerful, forms of heating. A 100 year old house might have 12 fireplaces, each of which, when loaded full of wood or coal, can output 10 kilowatts. Thats 120 kilowatts of heat - 500k btu/h. If upgraded to a gas boiler, that same house might be fitted with a 30 kilowatt system - 100k btu/h The same house outfitted with a heat pump might expect to get…

12 fire places? Is that a mansion or something? Or just poorly designed and not insulated in any way?
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