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Harnessing America's heat pump moment

heatpumped.org

341–350 of 571 posts

Re: Harnessing America's heat pump moment

#341
The real question is what the total cost of ownership and what is the payback period? Also there are regional climate differences that have to deal with very large temperature swings as well as very old poorly insulated houses. investing hundreds of thousands to re-insulate one's house, replace all the windows, excavate the heat sink and dispose of a furnace that is already working, so that one can buy a heat pump at greater costs than a furnace to achieve efficiency improvements that barely pay for themselves over thirty years when the same amount of money can be spent elsewhere. if it were such a great idea it would have already been done.

Re: Harnessing America's heat pump moment

#342

Earlier quoted context omitted.

that's odd because Ontario and Quebec are colder than most of the US and just these two provinces account for about one million heat pump installs per year since 2020.

Heat pumps can work great in the northern us. However the experience of europe mostly doesn't apply. You need backup heat of some sort to use a heat pump.

No, you don’t.

Cold climate heat pumps work just fine at even -30 C. In fact, many malls and offices in Northern Ontario are switching to heat pumps only because electricity is so cheap. What heat pumps really need in cold climates is reasonable insulation.

Re: Harnessing America's heat pump moment

#343

Earlier quoted context omitted.

No, no ductless magic without mini splits. I feel like a lot of people refer to heat pump systems interchangeably with ductless mini splits, so I wanted to clarify that. Maybe that's just an issue with the people I speak with, though.

What's the difference? They all work on the exact same closed loop evaporation cycle no?

Yes, the actual refrigeration and heating cycles are always based on compressing and decompressing a gas. But the gasses used differ based on temperature range, and further you can have air to air, air to water, or water to water for the heat transfer. The overall costs are the system can be very different based on whether you have a split unit that requires a single wall penetration, a central unit in the basement with ducting, or a geothermal system that requires digging deep trenches or wells. It makes for difficult conversation when some people are talking only about air to air minisplits when others are including all of these and more.

Re: Harnessing America's heat pump moment

#344

Maybe I have scar tissue from COVID prices but $20k to install a ductless heat pump vs. a $200 to throw a window A/C in or $700 for a portable heat pump. While I get that these heat pumps are better for the environment and much more efficient it's a last mile issue. The installers charge an arm and a leg and I'm not hurting enough to self install. I'm hoping the window heat pumps that just run off mains will be avail…

For comparison, I just bought a house here in Japan. Installed 6 minisplit heat pumps across various rooms in the house. All together it cost me 750,000 yen ($5,000) for the hardware and 90,000 yen ($600) for the install.

Another person living in Japan. Sounds about right. A unit from a good brand (daikin, mitsubishi) costs ~$800? More or less depending on the room size. We had them installed when we built the house, installation price included. Two are enough to keep our house cool or warm in any season (it's a well insulated house). We have another in the guest room, use it only for when guests stay.

Re: Harnessing America's heat pump moment

#345

Earlier quoted context omitted.

For comparison, I just bought a house here in Japan. Installed 6 minisplit heat pumps across various rooms in the house. All together it cost me 750,000 yen ($5,000) for the hardware and 90,000 yen ($600) for the install.

Do you mean 6 A/C units ? I. e. 6 outdoor and indoor units regardless, this is incredibly cheap

It's units in 6 different rooms (3 bed, office, living, dining) so 6 sets of units.

After reading some other comments I realize one vital detail is that they were installed in a renovated house that already had suitable holes to the outside and power outlets where the units were going, so the install job was just mounting the units, pulling the tubing and gassing it, no cutting things up or doing electrical work.

The price would at least double if we needed all the holes cut open, and I have no idea what the electrical work would cost.

Re: Harnessing America's heat pump moment

#346

Earlier quoted context omitted.

They are efficient but do not have as high of an energy output as a smaller and cheaper gas furnaice. Apart from that, the water temperature is lower, so you need much larger radiators. Due to the lower energy output, you also need better insulation or a relatively massive heat pump. And the tech was not around 20 years ago (for reasons unknown to me).

Is there a reason to use radiators and not just go straight to air to air pumps, which also have aircon?

[deleted]

Re: Harnessing America's heat pump moment

#347
post #344

Earlier quoted context omitted.

For comparison, I just bought a house here in Japan. Installed 6 minisplit heat pumps across various rooms in the house. All together it cost me 750,000 yen ($5,000) for the hardware and 90,000 yen ($600) for the install.

Another person living in Japan. Sounds about right. A unit from a good brand (daikin, mitsubishi) costs ~$800? More or less depending on the room size. We had them installed when we built the house, installation price included. Two are enough to keep our house cool or warm in any season (it's a well insulated house). We have another in the guest room, use it only for when guests stay.

Our renovation company had rip-off pricing on years-old models, so we just asked a few electronics stores for quotes. First looked up the cheapest online options as baseline pricing, and then used the in-store sale deals to stay at the same total price but get the units in the bigger rooms upgraded to fancier/higher grade options.

Re: Harnessing America's heat pump moment

#348
post #201

Everybody seems to agree that installation costs way too much. There's a few parts to this. Everything has to be carefully sized - power, pipe sizes, unit locations. You need to put a house's thermal profile (how much heat loss, how much air leak, how much thermal mass) along with the regional thermal profile into an engineering calculation which computes what you need. Thermographic inspections are a thing.[1] Usual…

Isn’t it important to right-size non-heat-pump installs anyway? Too large a system causes short cycling, humidity problems, temperature swings. I have read installers habitually guesstimate over size to over charge (rather than do the proper calculations).

[deleted]

Re: Harnessing America's heat pump moment

#349
post #201

Earlier quoted context omitted.

Isn’t it important to right-size non-heat-pump installs anyway? Too large a system causes short cycling, humidity problems, temperature swings. I have read installers habitually guesstimate over size to over charge (rather than do the proper calculations).

The reality is that this is all solving a problem that people don’t have. Forced air is a terrible way to heat a building yet thats how most homes are heated, and it is good enough for most people. If you perfectly size a furnace for the coldest days of the year, it is now oversized for the other 90% of days. The cheapest way is to install a multi stage heating/cooling system that works on first stage most of the tim…

[deleted]

Re: Harnessing America's heat pump moment

#350

Earlier quoted context omitted.

This. I had 12 contractors come out for an estimate. I insisted to each that I would only consider estimates accompanied by a Manual J (aka show your work). I got 4 estimates with a manual J, and one of them the vendor said ‘despite that the math says you need a 4 ton outdoor unit, I’m giving you two,’ and refused to budge on that. I went with a vendor who did the math and sized accordingly and my system works great…

If we’re trying to bring down cost the this is the issue with so many contractors coming out. The cost of sales is about 10-15% of the installation in the US. So thats $2-3k in California per heat pump Try to get an install for $600 like in Japan when you have to pay $2k to find the customer. Let’s have a lower cost sales process. Review 12 companies online, pick top 3, ask them to come out.

Wild that you put it on the customer to reduce the sales cost.

I can see it being reasonable to explain during the initial contact that you want the standardized estimate, once that happens it's not really on the customer if the contractor goes out to chase the business even if they know they aren't going to do it.

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