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Nine US states are teaming up to accelerate the adoption of heat pumps

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Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#171

Post by ajross »

aidenn0 wrote: post #156

Anyone know what sort of electrical requirements there are for these? We currently have a gas furnace and gas range. My electrical panel is full (we used up the last of it installing 220V for the clothes dryer), and the furnace is on the opposite side of the house from the electric panel, under a different roofline. I'm going to at some point get an electrician in to look at things and see what the options are, but m…

You don't need space in the panel as clearly you already have a circuit breaker for your existing air handler. It will be a bigger line though, my house in Portland got a central heat pump and handler that wants 40A.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#172

Post by nostromo »

cyberax wrote: post #131
nostromo wrote: post #114

I have mixed feelings about our heat pump system. Yes, it's efficient. But it breaks about once every other year. Last winter the compressor circuit board malfunctioned and cost $5k to fix. Two years ago it was another issue entirely. All of our savings have been lost to service calls. I'm not super price sensitive, but it's still a pain when the heat goes out in the middle of winter and all the service techs are boo…

> If we ever have to replace it, we're going to have to rip open half of the house to remove the heating lines. It'll be a nightmare. Why? Assuming you have a split unit, the lines are just copper pipes and will work with any other heatpump.

Potentially, yes. But when we asked about this we were told that not all heat pumps and head units are compatible -- so we seem to be locked in based on brand, model, and refrigerant type.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#173

Post by ecshafer »

Dowwie wrote: post #152
readingnews wrote: post #86

I just replaced a furnace... everyone I called for a quote would not touch a heat pump with a 20foot pole, or they wanted prices that were 2X what a separate furnace and AC would cost to install. It was very strange. This is the second home where I had this experience.. basically, they really did not want to install it. I ended up going with gas as no local person would install/warranty a heat pump, or, it was priced…

where are you located? I was quoted 14k to replace a gas furnace for a single family in NJ

Unless that's a massive furnace that's robbery. In philly I replaced my furnace for $6k 2 years ago.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#174

Post by mdasen »

One of the big problems with heat pumps in New England is that our electricity costs 1.7x the US average (https://www.eia.gov/electricity/monthly/epm_table_grapher.ph...).

If you're in the South, a heat pump makes perfect sense. You're going to want AC anyway and it'll be way more efficient and save a ton of money when you want heat. In most of the country, even if it gets cold your electricity prices are still a ton cheaper. Iowa/Kansas/Missouri/Nebraska get cold, but their electric rates are less than half ours.

Heat pumps do work into freezing New England temperatures, but they're a bit less efficient as it gets to zero fahrenheit. That wouldn't matter if our electric rates were more reasonable, but at our high rates a heat pump would probably cost me an additional $50/mo in the winter (compared to natural gas). That isn't so bad and our electric rates might come down as offshore wind actually starts happening. Plus it might actually be cheaper than gas given that mini-splits would mean I could choose which rooms I want to heat rather than heating the whole place as a single zone. Plus there's the option to get solar power to drive down prices.

But I think the biggest issue in New England (and California) will probably be the high cost of electricity. In most of the country, heat pumps are a huge no-brainer.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#175

Post by teaearlgraycold »

nostromo wrote: post #114

I have mixed feelings about our heat pump system. Yes, it's efficient. But it breaks about once every other year. Last winter the compressor circuit board malfunctioned and cost $5k to fix. Two years ago it was another issue entirely. All of our savings have been lost to service calls. I'm not super price sensitive, but it's still a pain when the heat goes out in the middle of winter and all the service techs are boo…

How cold are your winters? My heat pumps are doing fine but it’s NorCal so they never have to work too hard.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#176

Post by throw0101c »

Tarrosion wrote: post #85
moribvndvs wrote: post #77

Earlier quoted context omitted.

I’ve had one for three years. While I generally love it, it cools too fast, which means it sucks at removing humidity, actually increases it a little. The installer over-provisioned.

I've heard this before -- that oversized cooling units (whether standalone AC or part of a heat pump) mean muggy interiors in the humid seasons. But...why? I'd think that a fixed amount of air compressed in the compressor means a fixed amount of condensation runoff from the unit, and it wouldn't matter much whether it's a big unit running occasionally or a small unit running frequently. Why is that wrong?

It takes time for the humidity to be removed out of the air: a 'particular' cubic foot (metre) of air that passes over the coils can be cooled quite quickly, but won't be dehumidified as quickly.

So when the unit runs it can drop the temperature by the necessary (e.g.) 5F (2C), but it may only drop the humidity by 5%, when it needs to drop by (say) 10%. So a 'too-short' run-time can adequately cool the air, but not necessarily remove moisture.

It's also easier to generate 'excess' humidity by bathing/shower than it is to generate excess heat (cooking could generate both). So the humidity can creep up in value while the temperature stays more steady.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#177

Post by brewdad »

widdakay wrote: post #145
shadowpho wrote: post #123

Earlier quoted context omitted.

> It's now more expensive to fuel a vehicle with electricity than gas How is that possible? Even at 20c/kWh it's still a good 4x cost difference I though

PGE goes up to 66c/kwh during peak now and in San Diego I think is >70c/kwh. Off peak base is 34c/kwh for PG&E. Gas is $4.5-$5/gal so break even I think ends up being near 50mpg ish for a 300wh/mi EV.

I'm not in CA, so genuinely curious. When you quote 66 cents/kwh is that the marginal rate for an addition kwh or is that averaging in fixed costs? I pay about $20/mo just to have an active service line to my house, even if I were to shut off the breaker and not use any power. But my marginal rate is about 18 cents/kwh.

I would call my rate 18 cents but not sure if we are doing an apples to apples comparison.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#178

Post by sokoloff »

ajross wrote: post #157
epistasis wrote: post #95

Earlier quoted context omitted.

Your experience is extremely common. Residential HVAC contractors tend to be extremely conservative, and don't adopt new technologies quickly, or even attempt to understand them. I had some flexibility in time in replacing my 50 year old gas furnace, so I was able to call about 8 contractors before I finally found one who was comfortable with the tech and wanted to do it.

Yeah, it's not an innovative sector, though a lot of the blame belongs with the hardware manufacturers and not the installers. FWIW, the quotes I got for installation weren't that awful. But getting it hooked up to the Nest thermostat turned out to be a 2-day process and require a subcontractor to show up.

I've installed two Nest thermostats and there's industry standardized color-coding and functionality and Nest conforms to that. (I don't doubt that you had that problem, but I think that speaks more to the incompetence of the original installer than to the complexity of installing a thermostat with a screen.)

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#179

Post by cogman10 »

widdakay wrote: post #159
czbond wrote: post #133

Earlier quoted context omitted.

New to heat pumps. Can I replace sub-components of an existing AC system with a heat pump for benefits of both?

I'm surprised this isn't more common. The only difference between a heat pump and standard air conditioner is a reversing valve. These are usually $50-$100, and just require one more wire to the thermostat. In colder weather, defrost and fancier controllers are needed, but for mild climates the reversing valve is really all that is needed.

You are dealing with different pressures on the refrigerant lines, but honestly that shouldn't really matter all that much. You also need a bit of logic for if the condenser starts freezing over to temporarily reverse the flow (and turn off the home fan) to defrost.

But otherwise, yeah, almost identical and a little crazy they'd cost much more over a typical install.

Re: Nine US states are teaming up to accelerate the adoption of heat pumps

#180

Post by Fuut »

demondemidi wrote: post #101
TheBlight wrote: post #94

Earlier quoted context omitted.

How well do they function? Do they provide nice consistent heat? How's the noise? Sorry to clog up HN with a random request of a product quality review but I'm in the market right now to replace my furnace as well. Thanks.

Heat pumps need to come with an electric heater because pumps stop working below 30 deg F.

This is just not true at all.

Why do you even respond if you don't know enough about heat pumps?

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