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Home Office Projects Series: Air conditioner setup

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Re: Home Office Projects Series: Air conditioner setup

#161

Post by nonbirithm »

erik_seaberg wrote: post #136
nonbirithm wrote: post #124

Earlier quoted context omitted.

> First off - if you're renting - you're not putting holes in the walls that go to the exterior and there certainly aren't any already existing. I've never seen or heard of that in the USA - particularly for apartments. This is allowed in my apartment. My closest neighbor cut a hole in the door leading outside and affixed an air conditioner to it, then made a setup of plastic bagging to make it lead all the way to th…

Did their front door have a pet door? I can imagine venting hot air through that. Or maybe taking the original door off the hinges and putting it back when you move out, though landlords get cranky about not having working keys.

No, it was an actual hole sized to fit the nozzle of the A/C.

Re: Home Office Projects Series: Air conditioner setup

#162

Post by rsync »

yourapostasy wrote: post #101
amluto wrote: post #43

Earlier quoted context omitted.

> Having individual heating and cooling units (per unit gas heaters!) is stupendously inefficient. > Contrast this with a condo in Minneapolis that I own wherein heat and AC are central in the building and individual units can set their temperature to whatever they like - all run with tremendously higher efficiency. This needs some real data. There are a few central technologies that might be used. A condensing gas-f…

Make sure if you get a mini-split that you do the following around keeping the condensate drain mechanism going. I have yet to see a mini-split product manual/installation guide that gives detailed information on these operational issues. Many models let you run the condensate drain on your choice of right or left side. The unused side is often only supplied with a friction-fit drain plug. Over a period of many years…

"Buy a silicone sealant that carries a 20-year warranty. Buy a roll of "cork tape" ..."

What kind of pipe is this ? If it is standard dimension copper pipe, or schedule 40 PVC, etc., why not just cap it with a sharkbite endcap ?

Bonus: cap it with a sharkbite ball valve ...

Re: Home Office Projects Series: Air conditioner setup

#163

Post by dvcrn »

wlesieutre wrote: post #149
dvcrn wrote: post #148

I did a much easier solution for my airconditioner (also in Tokyo so everything OP said applies): I bought a broadlink rm mini3 (IR emitter) for For getting the temperature of the room, I use other devices (a netatmo weather station) and used their API to pull the current degrees into a textfile on the server that is getting fed into the airconditioner plugin. Bonuspoint: I use the same IR emitter to control my TV. I…

You may not even need direct line of sight, as long as the TV can see what your remote is shining on. I know my remotes work from behind obstacles if I just aim them up at the ceiling. There are also inexpensive IR repeaters, intended to let you have your AV equipment stuffed in a closet and still be able to use all the remotes.

Oh nice! I know virtually nothing about IR so this is good information, thanks!

Re: Home Office Projects Series: Air conditioner setup

#164

Post by brendawalsh »

twblalock wrote: post #144
brendawalsh wrote: post #125

Earlier quoted context omitted.

These minisplit units are typically, at least 9k to 12k BTUs, and if it a multi-zone unit it can be 24k or more. I have yet to see a portable AC in the US that is more than 12k btus and as quiet as a mini-split. Mini-splits are more popular now in the US, but, for whatever reason, the US is really into ducted systems. I never understood why putting an air duct in a hot attic and an air handler in a hot garage made an…

A lot of central AC installations in the USA were added to the house some time after it was built, and the heating ducts were already there, so now they are used as the AC ducts too.

Do you have any more info about this?

I am curious about the history of residential HVAC in the US.

Re: Home Office Projects Series: Air conditioner setup

#165

Post by m463 »

amluto wrote: post #43
rsync wrote: post #24

Having individual heating and cooling units ( per unit gas heaters! ) is stupendously inefficient. I travel in Asia fairly regularly so this isn't new to me, but even after all of these years I can't believe I continue to see shiny, brand new "high end" condo buildings in Hong Kong, Shanghai, Tokyo, Seoul, etc., with individual AC units hanging out the window. Contrast this with a condo in Minneapolis that I own wher…

> Having individual heating and cooling units (per unit gas heaters!) is stupendously inefficient. > Contrast this with a condo in Minneapolis that I own wherein heat and AC are central in the building and individual units can set their temperature to whatever they like - all run with tremendously higher efficiency. This needs some real data. There are a few central technologies that might be used. A condensing gas-f…

> > condo in Minneapolis

> This needs some real data.

Minnesota Heating Degree Days[1]: ~ 500

Minnesota Cooling Degree Days[2]: ~ 8,000-10,000

I suspect heat pumps might reach practical limits with cold temperatures.

[1] https://upload.wikimedia.org/wikipedia/commons/d/da/United_S...

[2] https://upload.wikimedia.org/wikipedia/commons/6/6c/United_S...

Re: Home Office Projects Series: Air conditioner setup

#166

Post by asdfasgasdgasdg »

m463 wrote: post #165
amluto wrote: post #43

Earlier quoted context omitted.

> Having individual heating and cooling units (per unit gas heaters!) is stupendously inefficient. > Contrast this with a condo in Minneapolis that I own wherein heat and AC are central in the building and individual units can set their temperature to whatever they like - all run with tremendously higher efficiency. This needs some real data. There are a few central technologies that might be used. A condensing gas-f…

> > condo in Minneapolis > This needs some real data. Minnesota Heating Degree Days[1]: ~ 500 Minnesota Cooling Degree Days[2]: ~ 8,000-10,000 I suspect heat pumps might reach practical limits with cold temperatures. [1] https://upload.wikimedia.org/wikipedia/commons/d/da/United_S... [2] https://upload.wikimedia.org/wikipedia/commons/6/6c/United_S...

You reversed the numbers from your cite. Minnesota has much more heating degree days than cooling.

Re: Home Office Projects Series: Air conditioner setup

#167

Post by m463 »

asdfasgasdgasdg wrote: post #166
m463 wrote: post #165

Earlier quoted context omitted.

> > condo in Minneapolis > This needs some real data. Minnesota Heating Degree Days[1]: ~ 500 Minnesota Cooling Degree Days[2]: ~ 8,000-10,000 I suspect heat pumps might reach practical limits with cold temperatures. [1] https://upload.wikimedia.org/wikipedia/commons/d/da/United_S... [2] https://upload.wikimedia.org/wikipedia/commons/6/6c/United_S...

You reversed the numbers from your cite. Minnesota has much more heating degree days than cooling.

ugh. and now it's too late to fix the post. thank you!

Re: Home Office Projects Series: Air conditioner setup

#168

Post by twblalock »

brendawalsh wrote: post #164
twblalock wrote: post #144

Earlier quoted context omitted.

A lot of central AC installations in the USA were added to the house some time after it was built, and the heating ducts were already there, so now they are used as the AC ducts too.

Do you have any more info about this? I am curious about the history of residential HVAC in the US.

I only really know about it in the area where I live. AC was not generally included in new construction in the San Francisco Bay Area until the 1980s or 1990s. I wouldn't be surprised if a majority of apartments in the area still didn't have AC, based on the amount of window AC units I see.

However, most homes built in this area were built central ducted heating systems since the 1950s-1960s, when there was a massive building boom. Most older homes have had central heating added as a retrofit decades ago -- even old Victorian homes. So when people upgrade to AC today, it's very common to just use the same ducts.

It's not easy to find a house with a ductless mini split AC system around here. Most homes have a single-zone central system that cools the entire house.

Re: Home Office Projects Series: Air conditioner setup

#169

Post by yourapostasy »

rsync wrote: post #162
yourapostasy wrote: post #101

Earlier quoted context omitted.

Make sure if you get a mini-split that you do the following around keeping the condensate drain mechanism going. I have yet to see a mini-split product manual/installation guide that gives detailed information on these operational issues. Many models let you run the condensate drain on your choice of right or left side. The unused side is often only supplied with a friction-fit drain plug. Over a period of many years…

"Buy a silicone sealant that carries a 20-year warranty. Buy a roll of "cork tape" ..." What kind of pipe is this ? If it is standard dimension copper pipe, or schedule 40 PVC, etc., why not just cap it with a sharkbite endcap ? Bonus: cap it with a sharkbite ball valve ...

I'm not sure of the kind of plastic, it usually feels like some kind of HDPE.

I and others have had inconsistent results with SharkBite fittings for long-duration uses, for example see [1]. I suspect their O-ring is a potential weak link over a decades-span. YMMV. I like them for temporary (a few weeks to a few months) scenarios, but I haven't seen enough field experience like with PEX to know its design limits. I might use BoatLIFE Life Seal sealant in the future for the silicone if I run into another already-installed mini-split because I've seen it stand up very well to a massive amount of marine abuse in the short-term (3-5 years), but they don't warranty the sealant for longer than a year because of how much abuse it is normally put through, so I'd just be an n=1 experiment.

Personally, the next time I will install a new mini-split or similar that has such a alternate drain arrangement, I'm going to do the following before the installer arrives. Flip the unit upside down so the pipe points up, drop some JB Weld putty into the bottom of the pipe, then fill the rest of the pipe with West System Epoxy to make it truly permanent and out-of-sight-out-of-mind for any possible extreme lifecycle of the unit.

A friction-fit drain plug pointing out with the pull of gravity in a thermally-variant environment is just asking for trouble. If I had the right tools I'd probably fab up a replacement drain pipe out of stainless steel with threading to accept a silicone plug, and West System epoxy the pipe to the body of the unit, and see how that works.

[1] https://www.contractortalk.com/f9/sharkbite-fittings-do-they...

Re: Home Office Projects Series: Air conditioner setup

#170

Post by amluto »

m463 wrote: post #165
amluto wrote: post #43

Earlier quoted context omitted.

> Having individual heating and cooling units (per unit gas heaters!) is stupendously inefficient. > Contrast this with a condo in Minneapolis that I own wherein heat and AC are central in the building and individual units can set their temperature to whatever they like - all run with tremendously higher efficiency. This needs some real data. There are a few central technologies that might be used. A condensing gas-f…

> > condo in Minneapolis > This needs some real data. Minnesota Heating Degree Days[1]: ~ 500 Minnesota Cooling Degree Days[2]: ~ 8,000-10,000 I suspect heat pumps might reach practical limits with cold temperatures. [1] https://upload.wikimedia.org/wikipedia/commons/d/da/United_S... [2] https://upload.wikimedia.org/wikipedia/commons/6/6c/United_S...

I wonder if anyone has tried to commercialize a device that burns gas for combined heat and power and uses that power to directly drive a heat pump.

Alternatively, ground source heat pumps work decently well even in very cold places, but the installation costs can be high.

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