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Harnessing America's heat pump moment

heatpumped.org

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Re: Harnessing America's heat pump moment

#221

Post by ralph84 »

mastax wrote: post #201
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…

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).

They oversize because customers who have an oversized system generally don’t complain but customers who have an undersized system definitely will complain when it can’t get to and hold their desired temperature.

Re: Harnessing America's heat pump moment

#222

Post by kalleboo »

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…

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.

Re: Harnessing America's heat pump moment

#223

Post by nsxwolf »

wtallis wrote: post #166
pessimizer wrote: post #38

Earlier quoted context omitted.

Chicago days under -15°F since 2015: Jan 18, 2016 -21°F Coldest day of that winter Dec 19, 2016 -21°F Early-season Arctic outbreak Dec 27, 2017 -19°F Part of a prolonged late-December cold wave Jan 2, 2018 -23°F Deep freeze to start the year Jan 30, 2019 -30°F Coldest Chicago temp since 1985; “Polar Vortex” event Feb 14, 2020 -18°F Valentine’s Day Arctic blast Feb 7, 2021 -21°F Mid-winter cold snap Dec 23, 2022 -23°F…

What's relevant is not how cold it got on the coldest day of the year, but how warm it got on the coldest day, and how long it stayed cold. If the daytime high is mild enough that an undersized heat pump can keep the house at 72, it will take time for that house to cool from 72 to eg. 63 when the temperature drops overnight. And since the heat pump is still trying to keep the house warm, it'll take a lot longer for t…

It makes sense but I just wasn’t willing to trust that with my checkbook, you know? There’s how it’s supposed to work on paper and then a reality where I’m stuck with it.

The regular AC and gas furnace combo works and is cheaper so I stuck with that.

Re: Harnessing America's heat pump moment

#225

Post by dzhiurgis »

chongli wrote: post #169
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…

This is talking about cold-climate heat pumps. A $200 window AC isn't going to heat your house when it's way below freezing outside. $20k USD is insane though. I live in Ontario and we paid $12k CAD (pre-government subsidy) for a modern heat pump with a backup high efficiency furnace for when temperatures dip down to -40 or lower.

Actually its probably most efficient way because you have best control. That said having whole house ducted you also get benefit of fresh air via ERV (arguably more important than heating).

Re: Harnessing America's heat pump moment

#226

Post by dzhiurgis »

chongli wrote: post #212
danielsju6 wrote: post #207

Earlier quoted context omitted.

True. We have natural gas and an existing steam radiator setup though, for the two months a year window heat pumps can't keep up. The upfront investment alone would heat my house for 10-20 years. Honestly, just piling more insulation in the attic and doing an energy audit will probably put the ROI out another 10+ years... I'm hoping the newer window units that are being rolled out to the NYC market will be good enoug…

There’s another alternative: a mini-split. Larger than a window unit, with a refrigerant lines you run yourself but with the actual refrigerant pre-charged inside the unit, so you don’t need to handle it yourself (which usually requires a license). Mini-splits tend to be much cheaper than full installations.

2k NZD to install minisplit vs 160KWh per winter month to heat my bedroom. Thats about $150 in power or 16 yrs to pay itself at COP 5. Or install 1 additional $130 solar panel to make about 650 KWh per year.

Makes sense for living room tho.

Re: Harnessing America's heat pump moment

#227

Post by ssuds »

psunavy03 wrote: post #194
ssuds wrote: post #129

Earlier quoted context omitted.

The first point is very valid too. There was an energy commission study a few years ago, and up front cost is pretty consistently one of the biggest barriers to heat pump adoption. I think there's some nuance to that, though. Even replacing a furnace + AC in California amounts to tens of thousands of dollars! It's not that heat pumps are expensive, it's that construction work in general is expensive. When you frame i…

. . . and how many people do you assume own $3M homes? Good grief.

The median home in the SF Bay Area is $2M, so given that this thread is focused on California I think it’s a reasonable number to anchor on… https://www.sfgate.com/realestate/article/bay-area-metro-are...

Even if we changed the number to $1M, the overall point remains the same

Re: Harnessing America's heat pump moment

#228

Post by relaxing »

smileysteve wrote: post #156
darth_avocado wrote: post #57

Earlier quoted context omitted.

I’m in California, I have two heat pumps installed. I can sum up the problems as follows: 1. They are EXPENSIVE. The equipment itself isn’t that expensive tbh but installation is pretty expensive. The government subsidies have made sure that the contractors jack up their own prices by as much. 2. I end up paying more in utilities because electricity is very expensive and heat pumps aren’t nearly as good at heating in…

Re #2. Tuning a heat pump vs resistive heat is a much tougher game than it should be. In a moderate climate, I use my ecobee to ensure aux heat doesn't come on until it's below freezing, and it should only come on if something has gone wrong at that point too. Unfortunately, many thermostats by default will use resistive heat in relatively normal scenarios, of worse, when you've programmed home and away times intende…

In a moderate climate you should have no need for resistive heat. Why isn’t running the heat pump alone enough?

Re: Harnessing America's heat pump moment

#229

Post by relaxing »

EngCanMan wrote: post #220
yojo wrote: post #162

Earlier quoted context omitted.

It’s bonkers. I bought a pre-charged ductless mini split to DIY. Took my dad and I about four hours to do the install. So call it 8 hours of semi-skilled labor. The unit was $1350, I added a line set cover, pad and feet for another $200, and needed about $200 in electrical equipment - it was a long wire run and code requires installing a disconnect box. The only special tool was a hole saw bit for running the coolant…

Umm, I encourage you to do that math a little closer. A contractor would have to; Come to your house to quote, and only land 1/4 quotes maybe. Schedule the workers Order the equipment. Get an electrical permit. Pay for the truck and all the tools. Insurance for the company and trucks. Advertising costs Warranty and callbacks I can assure you that this is not the get rich quick scheme you may think it is.

Look up private equity buying up HVAC firms.

It is in fact a get rich scheme.

Re: Harnessing America's heat pump moment

#230

Post by [deleted] »

kalleboo wrote: post #222
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…

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.

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