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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

#381

Post by cmui »

samstave wrote: post #340
cmui wrote: post #45

Earlier quoted context omitted.

I totally get this concern. Any good piece of critical home infrastructure should be able to operate without the cloud or an internet connection. Following this logic the thermostat + heat pump combination can operate fine without the cloud. You leave some optimized behavior on the table like demand response and weather response, but everything else will work (you'd have to manually enter your TOU rate plan to get th…

Crazy idea: Pressure plates in the streets which are pressed when cars drive over them - pushing fluids through your coils, but connected to multiple units on either side. Harvest the kinetic energy of cars passing through the streets to apply pressure to pumps that feed fluids through the system, capturing that energy in a dynamo way? Put these plates in every high trafficked area. Piping the pumping action from par…

I like the out of the box thinking! Unfortunately I think this one doesn't quite pass first principles. Any pumping action from the vehicles would be extra work they have to perform, so you just shuffle the energy expenditure from your local heat pumps, to a fleet of vehicles.

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

#382

Post by phasetransition »

amluto wrote: post #311
cmui wrote: post #57

Earlier quoted context omitted.

I understand the concern around lock in. There is a technical hurdle to optimized thermostat variable speed heat pump interop. You have to turn the temperature error between setpoint and actual temperature into a compressor speed command and also factor in behavior such as defrost, compressor cycling limits, etc. So you have to have a communicating thermostat to fully utilize the efficiency of these variable speed he…

This doesn't seem at all worthy of anything proprietary, though -- a simple RS-485 or 10BASE-T1L protocol and a page of docs would do the trick. And if you build this, you can also sell the same hardware plus a BacNET or MODBUS gateway for a bunch of money to the commercial building management types :) Or you could support existing commercial 0-10V thermostats.

Upvoted,

BACnet already exists as an ISO standard: https://www.iso.org/standard/37298.html https://bacnetinternational.org/

The example application in the Ethernet Alliance one-pager on single pair Ethernet is HVAC: https://ethernetalliance.org/wp-content/uploads/2020/10/EA_T...

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

#383

Post by the_third_wave »

Those prices... out of this world? Can you explain to me how it is possible to get a 7kW air/air heat pump installed for a total cost of ~17.000 [1] Swedish kronor (~$1600 at current rate) for a fraction of the price of these things? These devices all come with networked remote control, most of them can be integrated into 'home automation' systems without problems, they tend to work down to around -30°C (-21°F) albeit with lower efficiency (as will these devices). All that is 'missing' is the 'air quality' claim - although several of these heat pump manufacturers make claims about their devices filtering the air, using ionizers to 'increase air quality' and such. What remains is the Apple/Nest-like design and the claim of better integration with thermostats. To me this does not explain the factor 10 price difference, especially given that the Swedish prices include the high Swedish value added tax (25%) as well as the installation costs. What am I missing?

[1] https://www.polarpumpen.se/varmepumpar/luftvarmepump/

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

#384

Post by Arch-TK »

samstave wrote: post #340
cmui wrote: post #45

Earlier quoted context omitted.

I totally get this concern. Any good piece of critical home infrastructure should be able to operate without the cloud or an internet connection. Following this logic the thermostat + heat pump combination can operate fine without the cloud. You leave some optimized behavior on the table like demand response and weather response, but everything else will work (you'd have to manually enter your TOU rate plan to get th…

Crazy idea: Pressure plates in the streets which are pressed when cars drive over them - pushing fluids through your coils, but connected to multiple units on either side. Harvest the kinetic energy of cars passing through the streets to apply pressure to pumps that feed fluids through the system, capturing that energy in a dynamo way? Put these plates in every high trafficked area. Piping the pumping action from par…

For a similar reason why riding a bike through sand is more difficult than on flat tarmac, this will require additional energy and you will pay for it in locally burned petrol. Moreover, it will be less efficient than if you just burned that fuel in a power station.

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

#385

Post by drusenko »

spaceguillotine wrote: post #348
aintgonnatakeit wrote: post #203

Earlier quoted context omitted.

Yes s/he is. Mitsubishi force you to use their Kumo Cloud controls, which are 1) expensive (a few kk) and 2) require cloud. Supposedly Mitsubishi is replacing Kumo with something else, but that just makes the problem worse.

you can get a converter to get Mitsu to work with any 24v AC controls PAC-US444CN-1, ive installed a few of them so the customer could use their existing Nest and Ecobee thermostats. I'm a former diamond certified Mitsubishi installer

I've used the PAC-US444CN-1 (at our house) and fully native Mitsubishi thermostat/controls (at our in-laws). The converter is better than a simple 2-stage set up but is still not as good, in my experience, as the fully native one.

It has to translate a 2-stage signal into a fully modulating output, and it still seems to do a lot more on & off with high fan speeds than I would like or would be most efficient (as an aside, yes I have verified that the dip switches are in the correct position on the converters).

On the other hand, the unit at my in-laws tends to blow gently but consistently which is both more comfortable and more efficient.

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

#386

Post by mjhay »

turtlebits wrote: post #15

Existing established companies offer centrally ducted heat pumps. You can purchase them direct, and are even sold by your big box home improvement stores. (search for "ducted heat pump) They are generally contractor only as homeowners generally can't DIY the 240v electrical and lineset hookup. What exactly is being improved upon by your startup?

Those established companies don't have units with smart thermostats that get bricked if the company goes out of business.

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

#387

Post by cmui »

potatolicious wrote: post #368
cmui wrote: post #210

Earlier quoted context omitted.

Yes, making spare parts and service work is super important. We'll likely set up regional distribution points for spare parts so anything critical can be easily sent next day.

What about labor? I'm pretty handy but there are definitely parts of my HVAC system where I'd be unable/unwilling to DIY it. I currently have a local HVAC contractor on-retainer for same-day emergency appointments - and honestly I don't think I'd be willing to consider anything less since my current heat pump is my exclusive source of heating in this house. I'm in a temperate climate so there's little actual danger,…

Yeah, good question. The system is not meant to be DIY. The same contractor that does install also offers service. Logistics for replacement parts is important we will have quick, easy access for contractors.

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

#388

Post by hummus_bae »

AkhSha wrote: post #374

Why are heat pumps suddenly getting so much attention? Here in Australia they have been common for at least the last 20 years. Most new houses have been fitted with heat pumps, or as we know them, reverse cycle air conditioning.

Not to start trash talk, but I believe that most of the ones here are scams.

They are effectively electricity generators, using electricity to heat and generate more electricity. In typical Australian winter even slightly below average outside temperature means they are generating more than they are consuming.

They definitely have a place, but they are not as good as they are marketed to be.

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

#389

Post by drusenko »

notJim wrote: post #246
s_tec wrote: post #128

Earlier quoted context omitted.

Well, that just makes it worse! OP strongly implies that there is no good variable-speed solution, but if the industry already has an assortment of products, what exactly are they even selling?!

I think you're misreading the OP slightly. There's no cross-compatible system for variable equipment, which is why the OP says you can't use variable speed equipment with Nest. Nest is basically a really fancy switch only. To use variable speed equipment, you have to use your manufacturer's proprietary system. I'm not positive this is right, but I'm pretty sure it's backed up by https://www.pickhvac.com/central-air-c…

The issue isn't that an open standard for fully variable speed isn't possible, the issue is that nearly all of the manufacturers to date have considered this proprietary (as they want to own the entire ecosystem from controls > equipment) and a purposefully boxing Nest, Ecobee, etc, out of being able to control it in order to sell more thermostats and trying to capture more value.

Only problem, their thermostats and apps really suck.

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