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Harnessing America's heat pump moment

heatpumped.org

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Re: Harnessing America's heat pump moment

#381

Post by dns_snek »

glxxyz wrote: post #177
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…

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…

> Net metering lets me 'store' excess from summer and use it in winter

FYI net metering is unsustainable for the grid and policies will probably change (reducing rates for energy, increasing rates for delivery fees to offset the "freebies") as soon as adoption reaches a critical mass.

Re: Harnessing America's heat pump moment

#382

Post by steveBK123 »

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…

Northeast US here.

My 30 year old central air which covers 1 floor of my home went out recently so I got a bunch of replacement quotes, most vendors I asked for both a traditional central air & a heat pump central air quote.

The quotes were generally 50% more expensive for the heat pump option.

Vendor A: $12.5k AC, $17.7K Heat Pump + extra electrical work for the heat strips.

Vendor B: $8K AC, $11K Heat Pump + they don't think the existing ductwork is sufficient for comfortable heating and would recommend redoing some of it.

And I wouldn't qualify for any tax credits because it doesn't cover full home (there are upper floors without ducts that already are on mini splits & baseboard heat).

Also worth noting the range of HVAC quotes for the same spec cooling in the same home are insane. Every quote I got seemed to widen the range.

Re: Harnessing America's heat pump moment

#383

Post by coffeebeqn »

dns_snek wrote: post #374
coffeebeqn wrote: post #363

Earlier quoted context omitted.

That’s wild. Is it something that plugs into a central air so not the usual consumer heat pump? I just got a nice heat pump in Finland for two floors with two indoor units for about $3000 with install. It should handle 99% of our heating needs. The most expensive units on the market are about $3000-4000 and for install I got quoted $1k fixed without shopping around. That includes drilling through two brick outside wa…

It would be helpful to provide the rated thermal power of your heat pump. You might need a 3kW heat pump while they need a 16kW one.

7.5kW - around 105m2

Re: Harnessing America's heat pump moment

#384

Post by SigmundA »

quickthrowman wrote: post #370
tonyarkles wrote: post #94

Earlier quoted context omitted.

Keep in mind that there's going to be a CoP associated with a heat-pump water heater. Depending on (a bunch of factors) that 1500W HPWH could approach the performance of a 6kW standard EWH.

Yeah, I neglected to compare my hypothetical 6kW EWH against a 1500W HPWH, and did it against a 1500W EWH. Heat pumps have no problem operating at a COP of 3-4, so the 120V 12A (1440kW) HPWH would be equivalent to a 240V 25A EWH (6kW)

AFAIK there are actually no 1500w HPWHs currently, the normal hybrid 220v models have a small 500 watt compressor thats very efficient and keeps the airflow requirements low which helps with installation placement and ducting if needed, then still have the electric elements if needed to boost.

The 120v model HPWH's I have seen do not have electric resistive elements and instead have around a 1000W compressor, so they recover faster purely on heat pump and can run off a standard 15 amp circuit while staying well under the NEC 80% rule which would be 12 amps, they are closer to 10 amps.

They do require more airflow and are generally noisier due to larger fans and compressor.

Then you have dedicated split system HPWH's like SANCO that use an outdoor unit like a minisplit and pull around 1800 watts putting well over 6kw into the water, these are probably the future or whole house heat pump systems that heat both water and air(and cool) as combined unit.

Re: Harnessing America's heat pump moment

#385

Post by otsegony »

monssooon wrote: post #297

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 compl…

I don’t know whether you can get a completley silent unit, but I can say that our Mitsubishi heat pump does make a high pitched sound while running. Although I am used to it now, I found it annoying until I got used to it. It is very different than the intermittent low pitched rumble of my oil boiler.

Re: Harnessing America's heat pump moment

#386

Post by wongarsu »

upcoming-sesame wrote: post #335
zemvpferreira wrote: post #320

Earlier quoted context omitted.

It’s very normal here in Portugal. If you looked carefully and weren’t picky about the brands, you could have 6 mini-splits installed for $3000 all-in.

Parent mentioned $600 for the install. I live in Portugal as well, paid around $500 for ~one~ mini split A/C install

I would expect that installing six is maybe twice as expensive as installing one. All the overhead of scheduling the technician, traveling to the location, getting the tools out, etc stay the same. Installing six is vastly more efficient and that should be reflected in the price

GP still got an amazing deal

Re: Harnessing America's heat pump moment

#387

Post by LgWoodenBadger »

upcoming-sesame wrote: post #310
kalleboo wrote: post #222

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

Mini-splits these days are available as multi-head (I think that’s the term) units, where a single outside unit can supply 2,4, or 6 units individually and independently.

They’re remarkable, and I would go for a mini-split system over a central unit 100 times out of 100.

Re: Harnessing America's heat pump moment

#388

Post by lotsofpulp »

potato3732842 wrote: post #355
jofla_net wrote: post #239

Earlier quoted context omitted.

Its most simply summed up as what I call the tradesman's protection racket. On one side of the coin you have any moron, calling himself a repair man which can and does end in disastrous jobs which can be unsafe. This though has much lower pricing. The flip side is, basically a protection racket where suppliers only sell to you if you have a 'loicense' and the hurdles required to become said VIP are so high, giving yo…

You think HVAC is bad, plumbers and electricians have their protectionism written into law in many states. You must pay for their stamp. "Here is what I have and it is demonstrably within code" is not sufficient.

>"Here is what I have and it is demonstrably within code" is not sufficient.

It is if you do it yourself. You need the stamp to be able to sell your services.

Re: Harnessing America's heat pump moment

#389

Post by yojo »

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.

The equipment is actually a lot cheaper if you’re a pro - the DIY pre-charged line-set adds about $500 over an equivalent unit. Pulling a vacuum and adding coolant is not hard, just requires specialized tools that still aren’t that expensive.

I mentioned warranty and insurance.

You don’t need to “schedule workers” if you are owner operating. Maybe you want a (non-skilled) helper to speed up the install, but you absolutely could install solo. That said, you will need a licensed electrician to run the circuit.

In my metro, hvac contractors can get ten-packs of permits for mini-split installs, and at most one out of ten is inspected. It’s a rubber stamp if you’re a pro, and the individual permit is maybe $50.

And that $5k I mentioned is the low bid, which you’ll only see if you know how to find contractors who aren’t private equity fronts. These guys are not advertising, but they stay busy by having the best price. There are shops that will happily charge you double for the same work.

I never said it’s a get rich quick scheme. It is just highly compensated for owners without requiring the level of expertise of something like a plumber or electrician. I’m curious what is happening in the market to support these margins.

Re: Harnessing America's heat pump moment

#390

Post by SigmundA »

crgwbr wrote: post #106
doctorhandshake wrote: post #98

Earlier quoted context omitted.

The notion that heat pumps don’t work at low temperatures hasn’t been true for years. I think you may be surprised to find that just about any heat pump you look at has good efficiency down to very low temperatures.

That’s true, but still doesn’t always make heat pumps the most cost effective choice to operate. For example, last winter I paid an average of $0.24/kWh for electricity vs $0.05/kWh for natural gas. Even if a heat pump had a perfect 4.0 COP all winter, gas would be ~15% cheaper. Electricity prices really need to come down before it will be viable for everyone.

This varies quite a bit based on location for instance here in Florida natural gas is $0.13/kWh while electricity is about $0.12/kWh, also where I live there is no piped NG so it would be propane delivered to a storage tank which is even more expensive.

Also the winters are mild here so basically everyone has either a heat pump or the further south you go it's just heat strips because heat is rarely used so not worth the cost.

So any kind of blanket statement about heat pumps vs gas heat would be folly, but due to improvements in cold weather heat pumps and solar power are allowing them to make much more sense in more places.

There are many advantages to decoupling fuel combustion from its energy use, burning NG at a power plant relatively efficiently with much better emission controls, then distributing on electric grid for use more than just heating, while allowing the home to heat from many different energy sources and allow for grid down backup as well.

https://www.eia.gov/dnav/ng/ng_pri_sum_a_EPG0_PRS_DMcf_m.htm

https://www.eia.gov/electricity/monthly/epm_table_grapher.ph...

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