Strongly considering converting my off-grid RV to a mini split need some help

[Daddy Tanuki]

What unit is that?

I now it was not directed at me, but I am using a 10000 BTU (14 tatami mat sized) Mitsubishi unit that is split phase 200/240 and it sips power. its almost cheaper to use the A/C than a couple of fans in the middle of the hot months. we don't really get that hot here maybe 28-30C at the hottest. We really use it more for humidity control, but when i use it to cool its really energy efficient.

 

[Supervstech]

Most people are unaware of what mini-splits are, unless they're exposed to HVAC technology. They don't even notice them when they see them in use - they're all over the place, small restaurants and shops, stores, etc. And they're silent. Even the outdoor unit is like 50db. If you point out the air handler for them they'll go "oh, is that what that is?" They're super popular in third-world countries all over the world where conventional high-capacity HVAC either isn't available or is too costly. They are especially adapted to retrofitting. You can put a mini-split nearly ANYWHERE.

The problem with mini's in America is the HVAC industry is built around sending out a guy or two in a service truck with a huge cost overhead. There's just not enough profit in mini-splits to make their business model work, so they poo-poo them. Or mark them up ridiculously. You can buy a 1-ton DIY mini for a grand, a HVAC contractor will quote you five grand for the same thing in a Toshiba, LG, or other similar product.

They'll stand there and tell you homeowners don't like them because SHE doesn't like the look of that air handler up on the wall, which is just pure BS. The truth is they just know they like ambient temps to be about 75 degrees. LOL They don't really care how that happens.

Wow… tough on us installers ain’t ya?

Any company charging 5K to install a 1K unit is either dealing with some complicated line set routing, or has a HUGE advertising budget to keep up.

I charge around $600 to install a “DIY” unit, and between 1200 and 2500 for the various other units, unless it’s a big unit, with distribution boxes, and complicated line set routing.

By the way, most minis can be paired with ducted air handlers, ceiling caskets, and wall hung units.

I don’t know any companies that “poo poo” minis… I will say, their air filtration system is for the birds. I like to install the ducted air handlers and install a proper filter setup.

 

[acdoctor]

I am a HVAC contractor. I own 4 mini splits all 12k btu the reason is 9k minimum output is about 4K. 12k minimum also is 4k. The one in my 8.5 x 24 carg trailer conversion is a cooper hunter 12k btu 120 volt 22 or 24 seer. Indoor mounted at 1 end blowing to the other. Runs between 275 and 550 watts usually. I run the fan on medium high in order to keep the air stirred through the entire trailer. I power it with a Growatt 3000, 5.1Kw diy LiFePo4. Cooing on batteries is great, demand goes down when the sun does. Heating not so much. It takes about 4 kw to run through a night in the teens. Also running 11kf fridge.

 

[Supervstech]

I am a HVAC contractor. I own 4 mini splits all 12k btu the reason is 9k minimum output is about 4K. 12k minimum also is 4k. The one in my 8.5 x 24 carg trailer conversion is a cooper hunter 12k btu 120 volt 22 or 24 seer. Indoor mounted at 1 end blowing to the other. Runs between 275 and 550 watts usually. I run the fan on medium high in order to keep the air stirred through the entire trailer. I power it with a Growatt 3000, 5.1Kw diy LiFePo4. Cooing on batteries is great, demand goes down when the sun does. Heating not so much. It takes about 4 kw to run through a night in the teens. Also running 11kf fridge.

4kWh… not 4K which would be either a $ figure, or a scientific temperature indicator…
There is a great thread on here about using the correct abbreviations in posts.

 

[Browneye]

I have the receipts guys, hard numbers, tech’s quotes chronicled. You are likely exceptions, and DIY’rs appreciate that.
I talked with and/or got quotes with more than a dozen contractors. Some of the comments would make your hair stand up.
I did find some really good ones though, now on speed dial.

 

[Browneye]

What unit is that?

Mentioned in post 5 - Mr. Cool DIY series. Costco has sold them, Home Depot, various other retailers, in fact I thought I saw a link in one of Will's templates. Ingram's Air and Water is the US distributor for the Miami importer. I've spoken with both entities about their products and distribution.
Ingram's has them in stock and shipping is included, provide technical support and warranty service. The DIY line is the only split unit I'm aware of that will warrant units installed by the homeowner - all others exclude that. And really, unless you have the gauges and tools and tanks and such, you need a HVAC tech to setup a standard split unit. As mentioned, some techs will provide this service for an owner installed system.

I decided to give one a try after being bombarded by HVAC sales people. Especially since the old gas furnace still worked great. When you replace an air unit in a conventional central ducted system you have to replace the air handler, so it makes sense to just replace everything. Our old central system was a Sears Roebuck from about 1971. Super loud and a real power hog. It finally quit. Probably just needed a motor capacitor, but I just threw in the towel. Ended up removing it, and the air handler over the furnace, and buttoned everything back up and left the furnace. It is running as I type this. ?

Anyway, I was so happy with the 2-ton unit I decided to replace the window unit in the back wing of the house. I got a 1-ton scratch-n-dent unit from Ingrams for $800, fixed it and installed it, and it's been fantastic. Like I say, it will freeze you out. It's on a 120VAC circuit.

My middle daughter is a commercial electrician, so she was able to tell me how to reconfigure the 240circuit from the old AC unit to where the main 2-ton outdoor unit was installed. Installed a circuit box and breakers, ran wire, outside disconnect next to the new condenser unit.

Couple'a pics of installing it. The hardest part was getting the rather large air handler up 10' with the lineset - we have 15' ceilings. The smaller 1-ton unit was much easier to install.

Hole for lineset - the hardest one was thru the outside stucco wall - it was over an inch thick!



Air handler up a ladder. The earlier style DIY units came with the lineset attached to the air handler - what a PITA. They come with quick-connectors now.





Outside condenser:

 

[Checkthisout]

Only thing I would watch is doing something to the 5vr that destroys its resale value if you ever plan on selling it.

Make holes, mounts etc in such a way they can be removed and plugged without it wrecking the look of anything.

 

[acdoctor]

The “K” I was in a hurry my eggs were getting cold. Most HVAC contractors are scared of electronics. These things are loaded up with them. ( Contractor tip, these need a quality surge device.) I have never replaced a board on one with a surge protector. But I have on several without.
The issue with prices is a Contractor has to be profitable or they won’t be around to repair it down the road. An individual can buy a mini split off the internet cheaper than a Contractor can from a distributor. ( The distributor has to be profitable or they won’t be around when you need warranty parts.) Good luck getting warranty parts from the internet supplier. My brother purchased two from the internet. I installed them. The paperwork said they had to be registered online with a Contractor’s license number ( mine )for the warranty to be valid, otherwise there is no warranty. Ever time he hit submit the page 404ed. If I by one from the distributor I go back to them and get the part, they bill and credit me end of story.
I am not saying the prices every contractor is handing out is justified but it cost a lot especially these days to run a profitable business with proper licensing and insurances. The one guy with a few tool and a truck but no works comp or liability insurance, not following codes because he doesn’t pull a permit can always under price the others doing it right. He’ll be around for a couple of years then disappear.

 

[Checkthisout]

The “K” I was in a hurry my eggs were getting cold. Most HVAC contractors are scared of electronics. These things are loaded up with them. ( Contractor tip, these need a quality surge device.) I have never replaced a board on one with a surge protector. But I have on several without.
The issue with prices is a Contractor has to be profitable or they won’t be around to repair it down the road. An individual can buy a mini split off the internet cheaper than a Contractor can from a distributor. ( The distributor has to be profitable or they won’t be around when you need warranty parts.) Good luck getting warranty parts from the internet supplier. My brother purchased two from the internet. I installed them. The paperwork said they had to be registered online with a Contractor’s license number ( mine )for the warranty to be valid, otherwise there is no warranty. Ever time he hit submit the page 404ed. If I by one from the distributor I go back to them and get the part, they bill and credit me end of story.
I am not saying the prices every contractor is handing out is justified but it cost a lot especially these days to run a profitable business with proper licensing and insurances. The one guy with a few tool and a truck but no works comp or liability insurance, not following codes because he doesn’t pull a permit can always under price the others doing it right. He’ll be around for a couple of years then disappear.

Don't defend yourself. There is always a homeowner who can do anything and gets mad when he has to hire a pro because he could just do it himself if he had the proper tools and know how.

Other than that he's just as skilled as the pro and doesn't understand why you're not showing up to his house for free.

 

[Browneye]

Don't defend yourself. There is always a homeowner who can do anything and gets mad when he has to hire a pro because he could just do it himself if he had the proper tools and know how.

Other than that he's just as skilled as the pro and doesn't understand why you're not showing up to his house for free.

Surely there are folks like this, but I don't find it to be the general rule.
For sure, no need to defend, mostly people understand that.

After a year my 2-ton wasn't cooling, so I had a tech out to troubleshoot - he charged it and tested, found a leak in one of the lines where it was welded to the flex line coupling. $125.
Called the 'internet supplier' and they sent out a new air handler under warranty, didn't want the old one back. Changed it out, but thought it probly lost some more freon, so had my guy back to charge and test. Another $125. That was three years ago.
I was never unhappy about paying him, I thought he under-charged and I told him so.

I'm still way ahead - I could buy replacements three times for what a contractor would have charged.

And yes, quotes were $4800 to $6000 for one of these, and they said they would not warranty them. One guy wanted to put two air units up on the wall and add an attic fan - eight grand for that one.

Early on in the solar game I got a quote for $37,000 for a 18kWh system. Another would install for free and sell me the power it made on a 'solar lease'. Uh...no.

And why we DIY.