Ductless HVAC Systems

[bonneyman]

I find this topic interesting. My sons house is cooled with 2 window units. One big unit that is "supposed" to cool the kitchen, living room and bathroom and a smaller unit for the master bedroom. He wants to replace the large unit with a DIY minisplit.

Guess who he wants to install it?

I learned a magic word many years ago - "NO!"   

[skfarmer]

Well he is about 80 acres ahead me doing tillage  and could have told me today so I suppose it will work out.thing is he is fully capable of running that tractor and i know very little about ac......

[Matt_T]

Yeah, the pre-made line sets seem to always be short unless it's on a spare bedroom where the cond unit is on the opposite side of the wall from the evap unit. Some installs I've seen had longer linesets - but didn't need them - but the installer(homeowner?) didn't mess with shortening and fittings and just left the excess lines coiled up out near the cond unit.

The "pre flared" linesets that are bundled in the packages being sold online are normally around 16 feet which isn't going to be enough for much more than straight out the back and down. But the flares aren't the greatest and the nuts they use are light. Best to cut the flares off and re-flare with the nuts furnished with the equipment. And you can buy longer linesets if you need them. Just have to read the installation manual because you'll have to weigh in additional refrigerant if you go over a certain length.

The actual DIY units are a fixed 25 feet which can't be shortened without opening the lineset and evaporator to atmosphere which defeats the whole DIY aspect. And using up 25 feet of lineset is going to take some planning to make it look good.

One other thing regards condenser placement. Do not hang one on a wall unless you absolutely have to. They will transmit low level noise/vibration into the building.

[Matt_T]

Well he is about 80 acres ahead me doing tillage  and could have told me today so I suppose it will work out.thing is he is fully capable of running that tractor and i know very little about ac......

You don't really need to know anything about AC to install a DIY unit. It's just pretty basic construction, mechanical and electrical. Buying the correct sized unit requires some knowledge but that's the kiddos problem

[bonneyman]

Well he is about 80 acres ahead me doing tillage  and could have told me today so I suppose it will work out.thing is he is fully capable of running that tractor and i know very little about ac......

You don't really need to know anything about AC to install a DIY unit. It's just pretty basic construction, mechanical and electrical. Buying the correct sized unit requires some knowledge but that's the kiddos problem

I respectfully disagree with you on this, Matt. I've been to far too many DIY mini split jobs where the guy was trying to save money and "all you AC guys screw people" and they installed the dang thing and it didn't work. Then they call me, and are in my face that a "repair" shouldn't cost all that much!
Sure, anybody with basic wrenching knowledge can do the mechanical install and hook up 220 volt leads but the evacuation and balance charge is not something the backyard mechanic can easily do. The refrigeration cycle is an experience as well as a finesse thing, and people are bound to get into trouble if they just wing it. I'd hate to say "anybody can do it" and then something goes south and they're left hanging with a fairly expensive paperweight that the dealer won't warranty.

[Matt_T]

I respectfully disagree with you on this, Matt. I've been to far too many DIY mini split jobs where the guy was trying to save money and "all you AC guys screw people" and they installed the dang thing and it didn't work. Then they call me, and are in my face that a "repair" shouldn't cost all that much!
Sure, anybody with basic wrenching knowledge can do the mechanical install and hook up 220 volt leads but the evacuation and balance charge is not something the backyard mechanic can easily do. The refrigeration cycle is an experience as well as a finesse thing, and people are bound to get into trouble if they just wing it. I'd hate to say "anybody can do it" and then something goes south and they're left hanging with a fairly expensive paperweight that the dealer won't warranty.

Seems like we're talking about two different things. I'll mostly agree with you about a DIYer installing a flared lineset minisplit. It does require equipment, and probably skills, beyond what an average DIYer will possess. Their choice whether to invest in tools, and themselves, or pay a pro to either install it for them or fix their screw-up.

The DIY units I, and presumably SK, are referirng to are set up for a DIY install. Lineset and Evaporator are already assembled, and sealed,and attach to the Condenser with some coupling things which supposedly don't allow any atmosphere to enter the system. Then after the Condenser is connected to the lineset you open the valves to release the refrigerant like you would after evac, pressure test, evac on a conventional install. Below is a link to the the "manufacturer" for more info if you, or anyone else, is interested.

https://mrcool.com/mrcool-diy/

[stokester]

Well... I pulled the trigger and had a Trane/Mitsubishi split system installed in my garage/shop.

I'm amazed at how quiet the units are, especially the outside one, I can hardly hear it running even standing next to it.  These next few days will put it to a good test with the 90+ degree temperatures and coastal Virginia humidity.

[goodfellow]

You're livin' the life Nick! Great system and well worth it. I'm stuck with a wall mounted window unit -- it does a fair job, but yours is sooooo much better.

[muddy]

Would love to put a few if them in our house.

Sent from the twisted mind of the Mudman

[walrus]

I've been running a mini split for years, more for heat than for AC. An open floor plan house makes for a perfect fit for one of these. I use it for shoulder seasons, fall and spring. Shut it off in the dead of winter. Ran most of July this summer . Fujitsu is what I have

[fatfillup]

Walrus, reading your post I am reminded of how different your climate is then most here and radically different than Bman's in Arizona or any of our southern members.  Your need for ac is small but heat is huge and goes on and on and on

[stokester]

You're livin' the life Nick! Great system and well worth it. I'm stuck with a wall mounted window unit -- it does a fair job, but yours is sooooo much better.

Yes the garage stays cool and if I need to work upstairs I use the window AC too.  Best of all the humidity is under control.

But a word of warning! My wife commented with the cool shop she could now spend more time in there with me 

My response was for her to check the sign on the door.

Full disclosure here... she had that made for me when we built it.

[DeadNutz]

Good one Nick. Wouldn't work for me as most the machinery belongs to the wife and her art studio is upstairs and the stairs are inside. We could of put the stairs outside bet then the snow and ice would have made them dangerous.

[stokester]

This last week gave me a good test of the new AC - passed with flying colors.  It was nice to work in the shop at a nice 77deg when it was near 100 with 90+ humidity.

[Jamesyarbrough]

Good choice. Mitsubishi are about the best there is. They are more expensive tho.

I didnt wiegh in on this because i wasnt here but the flares are notorious for leaking on mini splits. I hope your installer was up to date.