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Heat Pumps – The Well-Tempered Future of A/Cs

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Re: Heat Pumps – The Well-Tempered Future of A/Cs

#401

Post by doctorhandshake »

notyourwork wrote: post #303
doctorhandshake wrote: post #291

Earlier quoted context omitted.

This comports with my experience pricing out a similar sized mitsu system

Not sure if it's a bit over-priced, however, we replaced a gas furnace without A/C. The variable speed air-handler is amazing for constant low speed circulation and the energy savings with moderate temperature for 60-75 degree weather is incredible. Also, I have 15k BTU available for one or two additional head units. I opted for this approach instead of under-sizing the heat pump or assuming we'd need the extra head…

Kumo cloud is beyond terrible and requires wildly overpriced hardware to find that out. I’m so displeased with it I’m on the brink of organizing a class action.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#402

Post by pnw »

EdwardDiego wrote: post #351
nsxwolf wrote: post #193

When I needed a new air conditioner a couple years ago I was quoted $17,000 for a heat pump. I can only guess at that point whatever energy cost savings it would bring would never be realized within the service life of the system. I went with a $6000 standard replacement AC unit.

Wtf, I paid $2K USD for mine. How out of the ordinary were your heatpump needs?

The differences are usually overall efficiency (that Trane is one of the most efficient models, SEER rating of 29.5), noise and overall capacity. This was for a >4000 sq ft house with extensive west facing glazing, not an ideal scenario.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#403

Post by ashayh »

spiderice wrote: post #249
ashayh wrote: post #232

The article mentions the most important point towards the end: “The better you insulate, the less heat you need in the first place,” No heat pump will help if your house is leaky or under insulated.

You’re describing my situation. How do you de-leakify a house?

Aero barrier and/or spray foam for an existing home should work well. But they are not long lasting and are often not environmentally friendly. You can also look into exterior insulation.

If possible and if you have the funds, try to do a retrofit: https://ekobuilt.com/2019/04/24/retrofitting-an-older-home-t...

https://www.buildwithrise.com/stories/passive-house-retrofit...

You don't have to do all the the things to improve performance -- you can pick and choose.

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#404

Post by ashayh »

NiloCK wrote: post #283
ashayh wrote: post #232

The article mentions the most important point towards the end: “The better you insulate, the less heat you need in the first place,” No heat pump will help if your house is leaky or under insulated.

I have new heat pumps in a very old, under insulated, and leaky house. I didn't use my oil furnace last winter (the first since two additional pumps). My costs were about half of the previous year, and I'm sure my carbon footprint was much better as well. Can you say more about what your comment is supposed to mean?

Without fixing leaks and insulation, you've done the tech equivalent of throwing large amounts of resources at the problem rather than fixing the root cause :) Your CO footprint will be far better if you decided to fix the leaks & insulation.

This is a pretty broad topic, and you can watch videos from this channel to learn more: https://www.youtube.com/watch?v=dReyrSGokEQ

There are options to do a full passive house retrofit, or just add exterior insulation if you have the funds and inclination. Plus you can get better air quality with filtered air, lower mold/pollen issues, lower noise if you care about that and overall home comfort.

https://www.buildwithrise.com/stories/passive-house-retrofit...

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#405

Post by ashayh »

XorNot wrote: post #289
ashayh wrote: post #232

The article mentions the most important point towards the end: “The better you insulate, the less heat you need in the first place,” No heat pump will help if your house is leaky or under insulated.

And it's irrelevant. Everyone is like "but if you have better insulation..." well golly gee, guess I'll get right on that. Tearing out all my drywall? Re-sarking my roof? Cost-free! Definitely not hugely disruptive, invasive and expensive activities which stand a good chance of forcing me to move out of my house while the work is complete... People love throwing in about how effective insulation is, completely ignori…

There are other advantages to fixing leaks & insulation such as controlling humidity/moisture, lowering mold/pollen/dust, lower noise, adding better air filtration, maybe even better fire protection. By "lower" I mean you can eliminate some of these issues. Not to mention a far lower energy bill. I would not describe these as irrelevant to most people.

Depending on the house, location and condition, adding exterior or interior insulation and/or aero barrier, or spray foam could be more cost effective and not so invasive as you think.

https://www.youtube.com/watch?v=_nOI99ew5MM https://www.youtube.com/watch?v=eYjF1afRqvE

Re: Heat Pumps – The Well-Tempered Future of A/Cs

#406

Post by TheHappyOddish »

stephen_g wrote: post #310
nsxwolf wrote: post #193

When I needed a new air conditioner a couple years ago I was quoted $17,000 for a heat pump. I can only guess at that point whatever energy cost savings it would bring would never be realized within the service life of the system. I went with a $6000 standard replacement AC unit.

What size? The last split system I bought cost about AU$1600 installed ( ~$1060) for 3.5kW... Looking at prices now, even going up to a ducted 14kW Mitsubishi Electric heat pump/AC is only AU$5000 (before installation, and you would need to add ducts and vents etc. - that's just the controller, outdoor unit and in-ceiling unit, but still)... Is this in the US? Maybe the market is distorted just because not enough peo…

Yep, just installed a 6kw for $2475 (GST inc) and felt like I overpaid. GP is wild.
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