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Harnessing America's heat pump moment

heatpumped.org

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Re: Harnessing America's heat pump moment

#291

Post by Atheros »

jofla_net wrote: post #241
Animats wrote: post #192

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…

or you could, you know, wing-it, like they do overseas, and I tell you, the world does not end.

You're better off guesstimating yourself than trusting contractors. The contractors are incentivized to severely oversize any AC units they install or else people leave bad reviews on their pages/listings when the installed unit can't keep up the one day every two years that the temperature gets abnormally hot.

I did this myself and insisted on a unit half the capacity that the contractors wanted. Several flat-out refused. But it works perfectly! Approximately one day ever two years it can't keep up. Which means that all the other time it doesn't short-cycle. Perfect.

Re: Harnessing America's heat pump moment

#293

Post by matwood »

danielsju6 wrote: post #148

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…

COVID prices just aren't a good comparison. I needed to replace a tankless water heater and was quoted $4k. I laughed, paid $1100 for a top of the line one and had my neighbor help me who used to be a plumber. Took 30 minutes and a bottle of a tequila for my neighbor.

Re: Harnessing America's heat pump moment

#294

Post by nine_k »

danielsju6 wrote: post #148

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…

Of the $20k, let's assume $5k is the hardware. Now $15k is the work. Let's consider the installation a highly skilled job, commanding $100/hour. This is 150 hours, or a tad more than 6 business days for a team of 3, working with full load 8 hours a day.

Does a split system indeed take so much work? What is so effort-intensive?

Re: Harnessing America's heat pump moment

#295

Post by CalRobert »

danielsju6 wrote: post #148

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…

Why not pick up a few mini splits from Home Depot and slap them in yourself?

Re: Harnessing America's heat pump moment

#296

Post by CalRobert »

edg5000 wrote: post #261
kortilla wrote: post #238

Earlier quoted context omitted.

Then why aren’t they in 2/3 of houses

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?

Re: Harnessing America's heat pump moment

#297

Post by monssooon »

Question: I have just bought house and deciding heatpump vs oil. We have an autistic person in the house hold that is very sensitive to high frequency noises and perpetual sounds in general. He is used to an oil furnace turning on and of.

I fear for sound pollution from a heat pump.

Will anyone share their experiences with this? Even just a shuttle humming would be a disaster for our spectrum case.

Can we get a completely silent setup ?

Re: Harnessing America's heat pump moment

#298

Post by vanviegen »

caminante wrote: post #286
thelastgallon wrote: post #282

Earlier quoted context omitted.

Yes, lets talk about subsidies. Fossil fuels have had and continue to have the most subsidies. Fossil Fuel Subsidies Surged to Record $7 Trillion/year: https://www.imf.org/en/Blogs/Articles/2023/08/24/fossil-fuel... The wealth transfer you are alluding to, it is from the poor (everyone) to the rich (fossil fuel billionaires), isn't it?

Please avoid unwarranted "whataboutism."

This is not whataboutism though. It's comparing two alternatives on a relevant aspect.

Re: Harnessing America's heat pump moment

#299

Post by Nition »

nine_k wrote: post #294
danielsju6 wrote: post #148

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…

Of the $20k, let's assume $5k is the hardware. Now $15k is the work. Let's consider the installation a highly skilled job, commanding $100/hour. This is 150 hours, or a tad more than 6 business days for a team of 3, working with full load 8 hours a day. Does a split system indeed take so much work? What is so effort-intensive?

Absolutely not. A basic ductless heat pump takes three or four hours to install by a couple of workers.

Re: Harnessing America's heat pump moment

#300

Post by reppap »

mattmaroon wrote: post #210
glxxyz wrote: post #177

Earlier quoted context omitted.

It's the opposite for me, much bigger ROI on the heatpump than solar. Rural property, 10 years old, ~3,500 sq ft + basement, in Canada where summer can be above 30C (86F) and winter below -30C (-20F). Electricity costs (Canadian) 7.6 ¢/kWh off-peak and 15.8 ¢/kWh on-peak here. I spent C$40K (about US$30k) on a ground source aka 'geothermal' heat pump to replace furnace powered by propane tank. I kept propane for on-d…

Solar in northernly climates is still not practical. (I’m Canada adjacent.)

You can break even on solar panels in 10-15 years in Sweden where I live and we're pretty damn northerly.
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