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Heat pumps of the 1800s are becoming the technology of the future

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Re: Heat pumps of the 1800s are becoming the technology of the future

#461

Post by phyzome »

lll-o-lll wrote: post #192
phyzome wrote: post #144

> owners of drafty homes may need to take on the added cost of insulation when installing a heat pump Installing good insulation is also really important even if you're not using heat pumps! With bad insulation, you're wasting energy no matter what technology you're using.

If you live in a warm climate, I personally think insulation is the worst (excepting roofing). Not because of efficiency, but because you isolate yourself from nature! The traditional Queenslander (look up Bluey if you don’t know what I mean), has so much going for it. It allows airflow through the whole house, a protected outside to sit and be with nature, lizards coming and going, bliss! This hermetically sealed en…

In that warm a climate, I don't think gas furnaces would be used much in the first place...

Re: Heat pumps of the 1800s are becoming the technology of the future

#462

Post by operatingthetan »

nsxwolf wrote: post #446
operatingthetan wrote: post #176

Earlier quoted context omitted.

Good callout. Some people have the strangest reasons to hate high-efficiency ductless systems.

How do you go ductless in a 6000 sq ft home?

If it's an existing build with ducts, stick with that. If it's a new build, then like the other poster said, you add more units. See the top of any commercial building for example: heat pumps all over the place.

Another option is to supplement an existing ducted system with a ductless one adding additional zones where you might want conditioning over night. E.g. bedrooms where you want to sleep in cold A/C in the summer where the rest of the house can warm up a bit, or a person in the household who likes their room to be warmer than everyone elses in the winter.

Re: Heat pumps of the 1800s are becoming the technology of the future

#463

Post by mrexroad »

buildsjets wrote: post #357
hawaiianbrah wrote: post #307

Earlier quoted context omitted.

Wow, really? Prices seem much higher than that in Seattle. A friend got 3 handlers totaling 24k BTU for like 12 grand.

I got quoted 16 grand for the same 24k/3 zone system in the Seattle area by the guys who install thru COSTCO. I ordered the hardware myself for $4300, bought about $300 worth of tools, and installed it in one long weekend. It’s really not that difficult. Basic electric installation, some special technique and tools needed for the plumbing (University of Youtube can help), pressure test, pull vacuum, open the valves a…

This is the way. And don’t forget your refrigerant license, which is super easy/cheap to get. Some manufacturers will void your warranty if not installed by someone unlicensed.

Re: Heat pumps of the 1800s are becoming the technology of the future

#464

Post by mrexroad »

thedougd wrote: post #437
turtlebits wrote: post #381

Earlier quoted context omitted.

The problem with Mr. Cool is that their DIY claim is because you don't cut the lineset (I believe they give you 25 ft). Any excess length you're supposed to coil up and hide, which is not ideal- plus you'll lose efficiency.

I believe they now sell other size lines and extensions. I got hung up on the excess line set idea and did a full DIY install of a non-DIY model mini-split. I bought, borrowed, and rented a lot of tools, spent a lot of time researching and learning. I really wish I went with the DIY model. Despite that lesson, I may do it again when I finish my attic space, but this time I'll add copper line brazing to the list.

Was there anything beyond the extra time/effort that made you regret going with a non-DIY model? I’m considering doing the non-DIY in next year or so.

Re: Heat pumps of the 1800s are becoming the technology of the future

#465

Post by mrexroad »

EricE wrote: post #341
briHass wrote: post #218

Earlier quoted context omitted.

Interesting. The code for duct insulation in unconditioned spaces in the US is R8, and they're pushing for higher currently. They also recently undid a long held myth about ducts buried in insulation leading to condensation issues. Most areas now allow ducts to be buried as long as you have R19 above and below, or R30 above. When I just installed a ducted mini for 3 upstairs bedrooms, I surrounded my R8 flex duct wit…

lol - it's not a myth. It's physics: https://www.youtube.com/watch?v=Vufih-WN5R4

Fwiw, context of this video is metal duct work. You’re not going to see R-8 flex duct buried in R-30 begin to sweat when the AC is running. In terms of controlling the dew point, the duct is no different than the conditioned space at that point.

Like you said, it’s physics.

Re: Heat pumps of the 1800s are becoming the technology of the future

#466

Post by kwhitefoot »

ClumsyPilot wrote: post #414
riceart77 wrote: post #372

Earlier quoted context omitted.

Mid-efficiency furnaces are still commonplace in the US, and they don't have sealed combustion systems - they get combustion air from the indoor space, but they vent 100% of combustion products out. High-efficiency furnaces in the US made in the past 30 years or so use sealed combustion with intake and outtake to the outside. (North American high efficiency furnaces older than about 30 years were not necessarily seal…

> But yes, the GP is full of shit. Or you live insulated from shitty alliances and low income life. A friend's husband was killed by a faulty boiler, carbon monoxide poisoning. In 2015 I lived in a house where boiler ignition didn't work and you had to reach inside with a lighter. That unit was definately not sealed. UK only required consenser boilers since 2005, the ones before that used to air from inside your hous…

Condenser boilers and balanced flue are separate concepts. The house I bought in 1978 had balanced flue gas heaters but they were not condensing. Condensing boilers are an efficiency measure. Balanced flue boilers have been available in the UK since the mid sixties.

Re: Heat pumps of the 1800s are becoming the technology of the future

#467

Post by adgjlsfhk1 »

mixmastamyk wrote: post #456
adgjlsfhk1 wrote: post #376

Earlier quoted context omitted.

yes but it still will be a lot less efficient than a window

Windows help of course but often there’s not enough wind to make a difference.

that's what a fan is for.

Re: Heat pumps of the 1800s are becoming the technology of the future

#468

Post by Dylan16807 »

mrexroad wrote: post #460
Dylan16807 wrote: post #353

Earlier quoted context omitted.

Okay but that's not what I was asking. That much heat loss will affect the overall temperature.

He did answer what you asked, but I think you may be losing sight of the forest for the trees here. Maybe re-phrasing will help?

They explained how something could cause uneven spots and low average, as far as I can tell. Because those spots leak so much.

But I want to know if there is a way uneven spots could cause a problem without some effect tanking the average. What do uneven spots themselves do?

Re: Heat pumps of the 1800s are becoming the technology of the future

#469

Post by hawaiianbrah »

turtlebits wrote: post #451
thedougd wrote: post #437

Earlier quoted context omitted.

I believe they now sell other size lines and extensions. I got hung up on the excess line set idea and did a full DIY install of a non-DIY model mini-split. I bought, borrowed, and rented a lot of tools, spent a lot of time researching and learning. I really wish I went with the DIY model. Despite that lesson, I may do it again when I finish my attic space, but this time I'll add copper line brazing to the list.

As long as the unit is pre-charged, DIY installs aren't that bad. I've done 2 Pioneers at my home. I spent around $150 in tools.

Awesome, I’ve been considering installing a few myself but am not sure if that’s silly or not.

I’m mostly curious how these DIY units compare to Mitsubishi, which seems to be what all the installers recommend.

Re: Heat pumps of the 1800s are becoming the technology of the future

#470

Post by mrexroad »

EricE wrote: post #340
Gordonjcp wrote: post #146

Earlier quoted context omitted.

Why wouldn't you just lay insulation on the ducts, same as you do with water pipes?

Over insulation introduces new problems like condensation (which causes mold and other nastiness) https://www.youtube.com/watch?v=Vufih-WN5R4

Your statement is quite context dependent, and does not apply to most modern residential scenarios. “Over insulating” a flex duct is not going to cause condensation. Metal duct work in an unconditioned space can cause condensation. Wrapping it in (often thin) fiberglass insulation can increase condensation in certain conditions. Improperly vented attics (and/or air leakage from conditioned space) with metal ducts can cause issues.
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