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Home Office Projects Series: Air conditioner setup

techprowd.com

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Re: Home Office Projects Series: Air conditioner setup

#41

Post by dpeck »

7thaccount wrote: post #7
calvinmorrison wrote: post #2

I like that the schematics are included on the air conditioner. I have a few older appliances like this that have it, and it has helped me a few times replacing/diagnosing parts. I laughed a bit where he explains about "Humidity" and the temperature. I know Americans are fat and lazy and love our AC's, but if you spend any time on the east coast, it's a giant swamp. Life is pretty insufferable without an AC when you…

In Louisiana and Arkansas (probably several other states), the temperature can get over 100 Farenheit with super high humidity. This leads to "swamp @$$" without copious amounts of AC. Being comfortable requires AC in the home, car, and at work. In highschool gym class we would just sit in the shade under the bleachers during the summer (too hot to do anything) and be dripping sweat everywhere back in class. It was m…

As much as A/C is amazing, it’s the lack of moving air that makes me the most uncomfortable. I’ve always been surprised at how much of Europe seems to have no interest in fans, ceiling or otherwise.

Re: Home Office Projects Series: Air conditioner setup

#42

Post by Scoundreller »

pwg wrote: post #18
djanogo wrote: post #4

Where are the refrigerant lines, how did they run them from compressor to evaporator?, I thought the biggest issue with AC self install is filling the refrigerant and sealing those lines.

> Where are the refrigerant lines, how did they run them from compressor to evaporator? Look at this image from the blog post showing the post install view: https://www.techprowd.com/content/images/2020/09/image-24.pn... Notice on the left edge there is a large white "pipe" running from the evaporator unit down to a hole in the wall (the hole was already present and visible in other photos). The refrigerant lines are…

> refrigeration grade vacuum pump needed here

My understanding is that some of the DIY units had a built-in vacuum pump for this step.

Edit: never mind, I think I’m making stuff up in my head. But I could see it being a feature in the future.

What makes a vacuum unit “refrigeration grade”? Other than recovering what you’re vacuuming if you’re doing maintenance instead of a first install?

Re: Home Office Projects Series: Air conditioner setup

#43

Post by amluto »

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-fired boiler might exceed 95% efficiency if you imagine that losses in the hydronic pipes are minimal. An evaporative cooling tower has awkward-to-define efficiency because it consumes water, but I doubt it works very well in Miami. A giant air-source central heat pump might be reasonably efficient (COP around 4?).

But little modern heat pumps with variable-speed drives (often marketed as "inverters") can be very efficient indeed. Fujitsu will sell you a unit right here in the USA with SEER 29 or better, and the general trend is that the smaller units are more efficient than the larger units. (Yes, SEER uses ridiculous units.)

Additionally, in most markets, a reasonably efficient heat pump is both less expensive to operate than even a 100% efficient boiler and has lower greenhouse gas emissions.

Re: Home Office Projects Series: Air conditioner setup

#44

Post by hinkley »

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…

I was a bit surprised he bought two condensers instead of one large one.

I’m looking for a mini split currently and I found condensers with up to three separate coolant lines (although with the shape of my place. I might only be able to use 2 at once, and have to use a window unit on the other end).

Unit size (especially width) goes up much slower than BTUs, so the main value of two seems to be cooling your house in installments, which he isn’t doing.

Re: Home Office Projects Series: Air conditioner setup

#45

Post by [deleted] »

edgarvaldes wrote: post #34
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…

>attitudes towards thrift that make it inconceivable/impossible to pay for AC that someone else might be using (or misusing) Sounds somewhat similar to the opinion some americans have against free healtcare

[deleted]

Re: Home Office Projects Series: Air conditioner setup

#46

Post by Scoundreller »

jabart wrote: post #33
djanogo wrote: post #4

Where are the refrigerant lines, how did they run them from compressor to evaporator?, I thought the biggest issue with AC self install is filling the refrigerant and sealing those lines.

Units come pre-charged now. My new central air unit was pre-charged at the compressor for 50ft of line. You need to still seal the lines to the unit which requires something hotter than a propane torch(acetylene), then you should purge the lines with nitrogen, have HVAC gauges to verify the pressure holds, then evac with a pump watching the gauges again. Those are some pricey one-time use tools. Some mini-splits now…

When it comes to pricey one-time use tools, I’ve found that I can come ahead by buying online (used or from Asia) and reselling it locally once I’m done.

It’s the tools I keep that end up costing me. I might need that 2nd jack, 3rd ladder, always nice to have a bucket of 10mms, bike rack for changing tire 1x/yr.

Re: Home Office Projects Series: Air conditioner setup

#47

Post by pwg »

Scoundreller wrote: post #42
pwg wrote: post #18

Earlier quoted context omitted.

> Where are the refrigerant lines, how did they run them from compressor to evaporator? Look at this image from the blog post showing the post install view: https://www.techprowd.com/content/images/2020/09/image-24.pn... Notice on the left edge there is a large white "pipe" running from the evaporator unit down to a hole in the wall (the hole was already present and visible in other photos). The refrigerant lines are…

> refrigeration grade vacuum pump needed here My understanding is that some of the DIY units had a built-in vacuum pump for this step. Edit: never mind, I think I’m making stuff up in my head. But I could see it being a feature in the future. What makes a vacuum unit “refrigeration grade”? Other than recovering what you’re vacuuming if you’re doing maintenance instead of a first install?

Generally what makes it 'refrigeration grade' is the level of vacuum down to which it can pull.

Here are some examples of refrigeration vacuum pumps:

https://www.grainger.com/search/hvac-and-refrigeration/air-c...

Re: Home Office Projects Series: Air conditioner setup

#48

Post by s0rce »

kijin wrote: post #21
7thaccount wrote: post #7

Earlier quoted context omitted.

In Louisiana and Arkansas (probably several other states), the temperature can get over 100 Farenheit with super high humidity. This leads to "swamp @$$" without copious amounts of AC. Being comfortable requires AC in the home, car, and at work. In highschool gym class we would just sit in the shade under the bleachers during the summer (too hot to do anything) and be dripping sweat everywhere back in class. It was m…

We love to romanticize the past, when people supposedly did fine without energy-wasting gadgets. The oft-forgotten truth is that people in the past just died more. And still do, in many parts of the world that are surprisingly close to us.

Heating buildings still takes more energy than air conditioning (usually much larger temperature differentials), people in the past used an enormous amount of energy on heating. They just consumed and generated the energy locally in the form of burning fuel, probably wood and coal instead of using an electric grid or natural gas.

Also, I don't think A/C is any more of an energy wasting gadget than a heater. I can survive, moderately comfortable on a camping trip down to -10C, probably colder if I needed but I certainly wouldn't want my office/home to get that cold. Similarly, I don't want my house to be 30C with 85% RH.

Re: Home Office Projects Series: Air conditioner setup

#49

Post by brudgers »

calvinmorrison wrote: post #2

I like that the schematics are included on the air conditioner. I have a few older appliances like this that have it, and it has helped me a few times replacing/diagnosing parts. I laughed a bit where he explains about "Humidity" and the temperature. I know Americans are fat and lazy and love our AC's, but if you spend any time on the east coast, it's a giant swamp. Life is pretty insufferable without an AC when you…

Pretty much every AC in the US has schematics somewhere behind a cover plate because field service by ordinarily trained technicians is a part of the equipment's life cycle. Basically, it's a safety issue (it might even be a UL requirement, I just didn't go that far down the google rabbit hole beyond the UL White Book https://legacy-uploads.ul.com/wp-content/uploads/2014/09/UL-...).

Re: Home Office Projects Series: Air conditioner setup

#50

Post by squeaky-clean »

roel_v wrote: post #28
Nextgrid wrote: post #20

Earlier quoted context omitted.

A lot of consumer-grade ACs use IR-based remotes which can easily be connected into whatever automation solution you have with something like a Broadlink bridge.

You can't query those for the current room temp, current settings etc. So then if you mix the OEM app & your home automation app, things get messed up. IR bridges are a hack in home automation, when buying new stuff avoid them.

Just my personal opinion, but the thermometer on an A/C unit is kind of worthless unless you sit within a foot of the unit. I prefer being able to read a sensor on the opposite side of the room, or even several sensors throughout the house, rather than one on the A/C unit. I don't use any OEM app at all, just my own. The OEM ones never do exactly what I want, so I have to hack something additional onto their features anyways. Home automation systems are really personal anyways though. I'm sure anyone here who's implemented their own has their own unique opinions about what's best ;)
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