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Harnessing America's heat pump moment

heatpumped.org

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Re: Harnessing America's heat pump moment

#481

Post by bradgranath »

giobox wrote: post #452
LgWoodenBadger wrote: post #387

Earlier quoted context omitted.

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.

> where a single outside unit can supply 2,4, or 6 units individually and independently In my current home, I have two "heads" attached to a single outside unit, but they cannot operate independently beyond setting different fan speeds or closing the vent really. If one of the mini-splits is set to heat and the other switches to cooling, they will booth start cooling, or vice versa, the head units just blindly blow a…

An extra clever system would include every temperature controlled appliance in the house. Heat could be exchanged between the hvac, water heater, refrigerator, and oven.

When the oven is done cooking it can dump heat into the water heater (and or furnace in the winter). The fridge and HVAC could dump heat into the water heater before pumping it outside in the summer.

Re: Harnessing America's heat pump moment

#482

Post by deinonychus »

drob518 wrote: post #450
danans wrote: post #409

Earlier quoted context omitted.

Compared to a conventional A/C compressor (which they replace), heat pump compressors are much smaller, quieter, and less ugly. As for the indoor units, they can either be the "ugly" ones (the indoor head units visible on the wall), recessed "cassettes", or they can use traditional A/C air handlers in a utility room to distribute conditioned air via existing duct-runs and registers. There are also companies like Quil…

I was curious about sound for both the indoor and outdoor pieces. The outside condenser for my current AC is very loud. Are the heat pump units quieter, and if so, why?

Speaking as an apartment dweller, my new apartment's ductless setup is much quieter (inside) than my old apartment's blower. At the old place, the fan was either on or off and must have added another 10 or 20 db of noise forcing you to always keep the TV remote nearby in case the fan turned on or off. It's very convenient that I can control my ductless unit's fan speed with a remote.

Re: Harnessing America's heat pump moment

#483

Post by deinonychus »

ericpauley wrote: post #435
SoftTalker wrote: post #408

Earlier quoted context omitted.

That doesn't square with the fact that new rentals are built with granite countertops and stainless-steel appliances. Tenants do shop around on the basis of amenities.

Sure, but those amenities are highly visible. Lots of units have a stainless dishwasher exterior, but most will still be the landlord-special plastic tub inside. Who is shopping around based on whether or not there’s a heat pump? I would consider myself relatively well-educated on this and still the heat/cooling source is an afterthought.

Honestly the ductless mini split system in my new apartment was a big factor for me. But it was the first time I'd seen one over here in the mid-atlantic.

Re: Harnessing America's heat pump moment

#484

Post by thelastgallon »

caminante wrote: post #398
Scene_Cast2 wrote: post #362

Earlier quoted context omitted.

Theoretically yes, in practice no. There is (according to my sensors) a fairly large CO2 increase inside a room when a modern furnace (with external exhaust) is running. I've confirmed this with several units (all made in the last 10 years), and it's not that the windows are closed - when the furnace turns off, the CO2 drops. And it's not that the exhaust is placed in a bad spot either.

> There is (according to my sensors) a fairly large CO2 increase inside a room when a modern furnace If this is happening, then you shouldn't be using that furnace/room! Something beyond the furnace is not configured right.

Yes, fossil fuels are the best to keep pollution away, just need to installed perfectly, configured and maintained regularly, monitored to make sure everything is running correctly, and have additional properties lying around vacant just in case there are leaks, misconfigurations, poor installation, etc. But we must use fossil fuels, there are no other options!

Re: Harnessing America's heat pump moment

#485

Post by JeremyPOsborne »

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?

2-3 hours planning, parts list, client management,

4-6 hrs to run electrical,

2-4 hrs to mount condenser,

4-8 hrs for medium line set,

4-8 hrs air handler, duct, platform integration,

1-2 hrs with thermostat and condensate protection,

1-2 hours nitrogen testing and pull vacuum,

1 hr documenting photos for incentive programs,

1 hr spending time educating customer about the system.

Messing up a parts order and figuring out a solution 4 hrs too often.

Total: 28 hrs, or 2-3 days of 2 people depending on the travel from their shop to customers home. I agree. Let's get that down to 12-16 hrs or single day and the best shops and installers can do that.

CA Labor law allow about 6-7 hrs of work on site as installers often have to start at their shop.

$3-4k of labor cost for small-mid size. Best might be be 2-3K labor cost. Minor equipment 1-2K, permit and testing required $1K. Then 50% gross margin is the target, net costs $2.5K indirect labor, $2K sales cost, project management, trucks, insurance, software, 10-20% net margin.

Just added the details in a comment above. https://news.ycombinator.com/item?id=45705876

Re: Harnessing America's heat pump moment

#486

Post by dzhiurgis »

chongli wrote: post #337
dzhiurgis wrote: post #303

Earlier quoted context omitted.

I do heat house main (using hp) just for comfort (and because it’s cheap). And I come from further than saaskwatch so I know what freezing pipes mean haha. My point tho is - hp’s are not panacea in my use case.

Heat pumps are not inherently expensive though. It depends on how competitive (or not) your HVAC industry is. Sounds like New Zealand has issues with this (probably due to being a small market).

High cost of labour is what screws us here in NZ. Tons of cheap heatpump from china sans tariffs and pretty much every house is required to have one.

I’d imagine similar in Canada. Either way whenever we discuss energy we should clarify where we post from since circumstances differ wildly.

Re: Harnessing America's heat pump moment

#487

Post by thelastgallon »

caminante wrote: post #278
thelastgallon wrote: post #266

Earlier quoted context omitted.

I'm jealous of your financial learnings. However, your model is not accurate as it doesn't factor in the 4 degree improvement in comfort and indoor pollution from propane furnaces: Propane furnaces can cause indoor pollution through the release of pollutants like carbon monoxide (CO), nitrogen dioxide (\(NO_{2}\)), and benzene, which are byproducts of combustion. It also doesn't include the negative externalities bec…

I agree it's important to watch for these things. For externalities or immediate health benefits, heatpumps are pretty defensible. However, solar isn't a saint. Rare earth/mineral mining is hazardous plus only a fraction of solar panels are getting recycled properly. > this is doable in harsh Canadian winters with negligible solar and it breaks even It's doable alright. OP got subsidies (See comment re: risk free loa…

> However, solar isn't a saint. Rare earth/mineral mining is hazardous

Solar cells are made of silicon, not rare earths.

For solar, you need to mine ONCE for 25 - 50 years. Fossil fuels are burnt every second continuously. Perhaps you can do the math if its not obvious?

Re: Harnessing America's heat pump moment

#488

Post by thelastgallon »

caminante wrote: post #369
zbentley wrote: post #328

Earlier quoted context omitted.

I hope we can agree that fossil fuel consumption is something to be avoided. Subsidies are an effective means of incentivizing people to avoid fossil fuels. If you believe the externalities of solar are a problem, what do you propose to do instead? Should we subsidize some other alternative? Redirect resources from oil to nuclear? Other?

>avoided [entirely?] You're making different/absolutist arguments. Even the most ardent electrification proponents agree that you can't replace downstream chemicals/materials. As for subsidies, you're thinking too narrow if you feel it necessary to only spend limited government budget on energy to improve lives.

> As for subsidies, you're thinking too narrow if you feel it necessary to only spend limited government budget on energy to improve lives.

But, its perfectly okay for govt to spend on fossil fuel subsidies? You draw the line when the subsidies are for solar, heatpumps, etc?

Re: Harnessing America's heat pump moment

#489

Post by thelastgallon »

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."

You brought up subsidies. I updated your understanding of subsidies. What is this whataboutism you are talking about?

Re: Harnessing America's heat pump moment

#490

Post by JeremyPOsborne »

bradgranath wrote: post #476
steveBK123 wrote: post #405

Earlier quoted context omitted.

Central air system with indoor blower & outdoor condenser generally don't come with pre-charged lines so self-install without certification isn't really an option in US.

It's not just certification/permitting. The manufacturers often state that the unit must be verified to be installed by a qualified technian or the warranty is void. Around here anyway, I was getting quotes of 20k for the install & equipment of a central air handler and the outdoor unit. I'd be dead before the thing paid for itself in electricity cost savings. $20,000 ÷ (~90yrslife - 40yrsold) = $400 / year of necces…

Most don't have a payback if the cost of electricity is too high. Let's make them lower cost up front and lower running costs so it's a no brainer when replacement is due.
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