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How a heat pump works

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Re: How a heat pump works

#261

Post by mikeyouse »

Casteil wrote: post #248
nly wrote: post #225

Earlier quoted context omitted.

- Better than resistive electric heating for the grid. Gas is going away so this is a problem that has to be solved anyway. - Economies or scale will solve the repair and maintenance burden... hell, it's not like a gas boiler is maintenance free...fucking things requiring serving every year and break down all the time in the UK. - almost noone has a generator when the power goes out anyway. This is a very wealthy Ame…

- Sure, at least when it's not super cold. Electrical grid may be a "problem that has to be solved" but it's one that carries staggering price tags and will have to be gradually transitioned into over decades. Natural gas will likely still be used as a heat source for many well into the late this century if not longer. - Gas boilers are far simpler units. Less moving parts, simpler electronics, all in all fewer point…

Only a vanishingly small section of the country has design temps below 0º, and even less have design temps below -10º (https://cdn-codes-pdf.iccsafe.org/bundles/document/new_docum...). Places like Boston that seem cold have design temps of 10º, Chicago is at 2º, Portland, Maine at 1º, etc. etc. (https://codes.iccsafe.org/content/IPC2018/appendix-d-degree-...)

A solution doesn't work in 100% of areas can still be the best one in the 95% of the places that do make sense!

And to your cost concerns, there's a bunch of Federal money (being deployed by the states) in the IRA to specifically pay for low-income Heat Pump upgrades.

Re: How a heat pump works

#262

Post by kevstev »

nashashmi wrote: post #125
snuxoll wrote: post #104

Earlier quoted context omitted.

> this is a no brainer in milder climates which is why I have a heat pump and no gas furnace here in FL even though I have gas to the house for other uses. They're a no-brainer in every climate. Newer heat pumps can handle fairly cold temperatures (-13°F) pretty easily, there may be a loss in efficiency but in the majority of the world it doesn't stay that cold. A few days of lower than normal efficiency, and at wors…

Ok! I am genuinely interested in how heat pumps are more efficient. My online search led me to calling heat pumps more efficient when compared to electric heaters. And better in other ways compared to gas burners. But lord's sake, they were all upselling marketing sites for heat pumps. I am looking for genuine research, and not from paid mouth pieces. Majority of the comments here seem like agents of heat pump indust…

Did you watch the video linked on the highest rated post on this thread? The one from technology connections? It explains it all very well.

I am happy you have an open mind, but the fact that you are trying to tear the technology down when you apparently have no idea how it works or what it even is- hopefully you realize that it is also used for air conditioning, and is essentially just an air conditioner running in reverse... I hope this is a learning experience for you.

At the very least it gives me hope that those trying to tear down this technology are just ignorant, I had real suspicions that they were agents of the fossil fuel industry, or this was something Fox News and the like decided to target and is now being parroted.

Re: How a heat pump works

#263

Post by barbazoo »

pkulak wrote: post #136
yreg wrote: post #6

Technology Connections has a good video on heat pumps. (Actually several of them, I link the newest one.) https://www.youtube.com/watch?v=MFEHFsO-XSI

I just found this guy too. He answered a lot of questions I had about efficiency and use below freezing. https://youtu.be/fxEqVuiHhM0

Their main channel is http://youtube.com/user/matthiaswandel

Re: How a heat pump works

#264

Post by timerol »

ctroein89 wrote: post #205
timerol wrote: post #145

Earlier quoted context omitted.

NYCHA is currently running a contest to develop a heat pump window unit. All of the proposed units are expensive to get those contest dollars, but should come down in price after. https://www.gradientcomfort.com/pages/products-air-condition... https://www.achrnews.com/articles/147122-midea-heat-pumps-to...

I have two heat pump window air conditioners installed in my apartment, with cooling, heating and resistance electrical heating: https://www.frigidaire.com/Home-Comfort/Air-Conditioning/Win... . The problem is that the tech is so poorly advertised, that I had to double-check the specs on manufacturer's website that this model was, in fact, a heat pump. Most people don't know that heat pump window units already are an…

I have seen units like that Frigidaire before, and can never tell whether it's actually a heat pump, or just an AC/resistance heat combination.

Edit: Nevermind I'm an idiot. From the spec page of that unit: BTU (Cool): 11,000 BTU, BTU (Electrical Heat): 3,500 BTU, BTU (Heat Pump): 9,900 BTU. Though the owner's manual mentions an extremely warm minimum outdoor temp: "The unit should be operated in a temperature range of indoor side 60°F - 90°F (16°C - 32°C), outdoor side 64°F - 109°F (18°C - 43°C)."

Re: How a heat pump works

#265

Post by jjtheblunt »

PaulDavisThe1st wrote: post #194
jjtheblunt wrote: post #12

Earlier quoted context omitted.

Wait till we have Heat Pumps built with Rust! But seriously i think it’s just that awareness hit a critical threshold so the hysteresis kicks in and articles proliferate. In both cases.

There's really no question that Rust will undoubtedly take over most heat pumps, sooner or later.

:)

Re: How a heat pump works

#266

Post by flemhans »

nly wrote: post #225
Casteil wrote: post #222

Earlier quoted context omitted.

He does, but he omits a lot of important considerations that make heat pumps impractical for normal Americans. If he touches on them, it's briefly - if at all, e.g.: - More expensive units, and more expensive to run power wise. It's always difficult to get adoption of new technology that's "better" but more expensive to buy & repair - to the point where RoI may never happen. - Power grid implications during very low/…

- Better than resistive electric heating for the grid. Gas is going away so this is a problem that has to be solved anyway. - Economies or scale will solve the repair and maintenance burden... hell, it's not like a gas boiler is maintenance free...fucking things requiring serving every year and break down all the time in the UK. - almost noone has a generator when the power goes out anyway. This is a very wealthy Ame…

Funny you think it's a wealthy American perspective to have a generator for outages. My thoughts went in directions of wealthy people in Bangladesh or India.

Re: How a heat pump works

#267

Post by jeffalyanak »

kenmacd wrote: post #233
pkulak wrote: post #224

Earlier quoted context omitted.

Are you thinking 10 degrees Celsius? I think all his numbers are Fahrenheit.

He's located in NB, so I assumed it was Celsius. To check I just compared them to the Environment Canada data it seems to match pretty close for NB in Celsius.

Edit: nevermind, thought this was still about Technology Connections.

Re: How a heat pump works

#268

Post by ptmcc »

megaman821 wrote: post #91
oceanplexian wrote: post #85

Earlier quoted context omitted.

An overlooked benefit is that they actually improve comfort over a boiler in a dry climate, so if you live somewhere with low humidity they help keep the air less dry. They also give you heating and cooling.. for places that don’t have Air Conditioning it’s a worthwhile upgrade.

I assume in home that don't have ACs, that they also don't have ducts. Do these ductless homes filter their air, control home humidity, or bring in fresh air from outside?

My ductless house has a gas combi water heater/boiler and hot water circulation system to in-wall radiators with simple blower fans.

The house also has an exhaust fan on a timer, paired with small vents on several windows around the house, to cycle in fresh outside air. But practically for much of the year we just open the windows for fresh air since we live in the temperate PNW climate, wildfires aside :(

I looked in to installing a minisplit heat pump system last year, but the quotes I got were outrageous ($25k+) plus as a retrofit it's not the most elegant integration. Someday I'd like to do the conversion and ultimately decommission the gas boiler, but at that price tag it's not happening soon.

In the short term I bought one window AC and one portable AC for a combined ~$1000. It's not ideal but we only have a few weeks a year where cooling is really needed, and a few more where it's a nice luxury but not a necessity.

Re: How a heat pump works

#269

Post by slfnflctd »

fullstop wrote: post #129
slfnflctd wrote: post #79

Earlier quoted context omitted.

What's the payback time on something like that for a modest home in a place which can get significantly under 20 degrees (F) or over 95 degrees for weeks or longer? How effective is it at those extreme temperatures when it matters the most, and how does this affect maintenance costs? Additionally, there are multiple types of restrictions on where geothermal pumps can be installed, and navigating this can add to costs…

Obviously nobody can answer the long term cost differences between gas and heat pumps, since the cost of natural gas and electricity can change drastically over the lifetime of the unit. GP's comment was about the tech, though, and not the cost of said tech. It's absolutely not a perfect solution for all heating needs across the globe, the the technology is far better than GP is suggesting.

In my view, natural gas is only competitive due to externalized costs and the slowdown/freeze of nuclear energy deployment. I recognize it's the only option for all kinds of situations (my dwelling heat included), but for anyone thinking forward it should be excluded in future development where possible.

My main concern is the overall long term efficiency & affordability of renewable-friendly solutions, because competitiveness in those areas is what will lead to mass adoption. The point I was hewing toward is that I feel the heat pump advocates and providers need to make it more clear which situations are best suited for that solution and which are not, because it would benefit everyone.

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