Mini split AC?

[Baz]

Originally Posted by HardDrive

The third floor of our home was finished about 20 years ago. HVAC not tied to bottom floors, they installed a furnace(3rd floor level) with an AC unit at ground level. AC has had a leak, dye not showing up anywhere obvious, so leak may be in wall.

Long story short, considering removing the AC component of furnace, installing Mini split with dual room cooling. Not a huge space, a medium window unit can keep it cool enough in the main space, so assuming BTUs is non issue.

I'm in Ohio, and external unit would be on a north wall that gets real weather.

Any advice/guidance appreciated.

Some info here, too:

https://forums.pelicanparts.com/off-topic-discussions/1122946-window-air-conditioner-mini-split-my-garage.html

[masraum]

Originally Posted by David

Installation required a 220v circuit inside and out and a flare tool for the copper lines. Buy or pour a concrete pad for the compressor, drill a hole in the wall for the copper lines, attach the lines, hang the wall unit, open the refrigerant valve and turn it on. You don’t have to pull vacuum on the lines but I did and found a bad connection so good thing I did. I also put power switches inside and out to meet code for maintenance.

If little insulation I’d go up a little in size especially if a living space.

Where's that damn thumbs up button?

[URY914]

We need a mini-split sub-forum on Pelican. This topic seems to come up every few months. (light-green font needed)

[peppy]

I guess I'm the odd man on this. We put one in our kitchen and I hate the thing. Always dirty and mildews. I would never buy another one for a home.

[Baz]

Originally Posted by peppy

I guess I'm the odd man on this. We put one in our kitchen and I hate the thing. Always dirty and mildews. I would never buy another one for a home.

You are saying the inside component (the register where the air comes out) gets mildew on it?

Does anything else in your kitchen get mildew on it - or just the register?

I only get mildew in my shower stall and shower curtain. No where else in the house. Easily controlled by a periodic spray of Mold Armor.

[red-beard]

Originally Posted by HardDrive

The third floor of our home was finished about 20 years ago. HVAC not tied to bottom floors, they installed a furnace(3rd floor level) with an AC unit at ground level. AC has had a leak, dye not showing up anywhere obvious, so leak may be in wall.

Long story short, considering removing the AC component of furnace, installing Mini split with dual room cooling. Not a huge space, a medium window unit can keep it cool enough in the main space, so assuming BTUs is non issue.

I'm in Ohio, and external unit would be on a north wall that gets real weather.

Any advice/guidance appreciated.

Why not run an external copper line? When we replaced our AC units, they had to switch to the "New" Freon, one of the lines installed in the house was too small. They ran a new line and the small portion that would have been visible was installed in a conduit cover.

[peppy]

Originally Posted by Baz

You are saying the inside component (the register where the air comes out) gets mildew on it?

Does anything else in your kitchen get mildew on it - or just the register?

I only get mildew in my shower stall and shower curtain. No where else in the house. Easily controlled by a periodic spray of Mold Armor.

It's just the inside unit. I had a service call and the guy told me it needs to be cleaned every few months. Oh and it stinks like hell. They spray some kind of deodorizer in it and it helps for a while.
Nothing else in the kitchen has mold/mildew.

[Cajundaddy]

Yes Mini-split is the future.

We added one to our Oceanside condo and it transformed the space in summer. Easy install, super efficient, and dead quiet. Once the room is at temp it ramps down speed and energy use so it is only drawing maybe 300w while sleeping at night and the indoor sound level is around 40db. I use a similar inverter technology Midea 8000 BTU window A/C for a project room with similar results. Super quiet and efficient and it cost $350.

[Baz]

Originally Posted by peppy

It's just the inside unit. I had a service call and the guy told me it needs to be cleaned every few months. Oh and it stinks like hell. They spray some kind of deodorizer in it and it helps for a while.
Nothing else in the kitchen has mold/mildew.

OK thanks.

I've never ever heard of that being a problem for anyone who have installed these.

Maybe your unit is somehow faulty?

In any event - I wouldn't castigate the entire concept just because of this one issue you had, especially it being an apparent outlier.

Maybe reach out to the manufacturer?

[island_dude]

I installed a MRCOOL DIY unit in my shed. This unit is a heat pump as well. I only run it when I need to go out when its too hot or too cold. It works really well.

The installation process wasn't bad at all. I did everything. The tricky part was definitely connecting the coolant lines and getting them properly torqued. The lines are vacuumed out and sealed. They use special connectors to maximize the that you won't mess it up. All in all, I love the unit. It works great in hot or cold weather and the unit is rated at 20 SEER. It took ~6 hours to do everything. It was >90 degrees out so I was very happy when it started cooling right away.

A normal unit needs a vacuum pump and a little more care. That would put me off now.

Originally Posted by masraum

Ok, for you self installers. What's the installation like?

Our house is old and poorly insulated, but we've got a heatpump that was built/installed in 1991 that keeps us cool in the summer and mostly warm in the winter.

Downstairs is ~1000sqft. Upstairs is about 500sqft. Downstairs is main/full bath, kitchen, dining, living, and office. Upstairs is 2 bedrooms, tiny half bath and a central room. We currently have a single heat pump with with ducts to all rooms including another room that's going to end up being a closet.

It seems like it would be prohibitively expensive to put units in all of those rooms. Although I guess if I could do the install myself, we might save enough for that. Of course, that would mean a ton of installation.

[Cajundaddy]

Originally Posted by peppy

It's just the inside unit. I had a service call and the guy told me it needs to be cleaned every few months. Oh and it stinks like hell. They spray some kind of deodorizer in it and it helps for a while.
Nothing else in the kitchen has mold/mildew.

Sounds like the inside condensate line is not draining well. Confirm that the unit is installed very level and the drain is not pinched or obstructed. Standing water is the most likely source of the nasty smell.

[rfuerst911sc]

Went out to the man cave this morning , it was 40 degrees inside . I flipped on the mini split and set the heat at 70 degrees . One hour later at the far end of the garage it was 64 degrees .

This is a 24' x 26' space with 12' ceiling height . Pretty impressive performance I think . In my opinion a 2 ton unit is perfect for this space . That cold concrete floor is like a heat sink . Now that winter is here I am going to leave it on and set it at 61 degrees which is the lowest heat setting for this model .

[Baz]

Originally Posted by rfuerst911sc

Now that winter is here I am going to leave it on and set it at 61 degrees which is the lowest heat setting for this model .

I wonder if installing some kind of timer would make sense for your situation, Rick.

Similar to how one uses them for water heaters.

Guess you'd have to formulate some kind of schedule that meshes with your needs.

Or....because it is so efficient....maybe this is a non-issue....and leaving it at 61 is actually the ideal situation.

Just thinking out loud.....

[rfuerst911sc]

^^^ Baz because of efficiency I don't mind running it at the low setting . It just doesn't consume that much electricity . Being retired I randomly go out to the garage when I want to . A timer would be a waste . But I appreciate the thought and Happy Thanksgiving 😁

[Cajundaddy]

Once it reaches set temp it rolls back energy usage to simply maintain at maybe 200w instead of 1500w at full power. This may be the most efficient way to keep the garage useable.

A very different beast from a ceramic or gas heater that cycles on and off at full power to maintain the set temp.

[David]

I cleaned mine for the first time this year. About 11 years over due. I removed the housing and brushed and vacuumed the fins and wiped everything else I could get to. I can see how the tape on bag to capture spray on cleaner and water spray would make for a better job.

[spuggy]

Originally Posted by rfuerst911sc

Now that winter is here I am going to leave it on and set it at 61 degrees which is the lowest heat setting for this model .

My Daikin's minimum setting is like 68F, IIRC. LOL...

A tad cozy for the garage (plus it'll never get there if its low teens outside, so will just run 24/7); in winter only really concerned about pipes freezing - this isn't my living room. I'm also good with turning the heat on manually if I'm going out there...

Interfaced to the mini-split via a CoolPlug/CoolLinkHub unit from CoolAutomation. Had to add the Daikin add-in board (cheap enough on Flea Bay).

Result: I could control the mini-split directly from a web/phone app (CoolRemote). Which had the same stupidly high minimum settings (corresponding to the built-ins for the mini-split, I suspect).

The last piece was to integrate to a Nest (provides all kinds of smarts and/or scheduling I don't actually use/need). And then run that in ECO mode.

So now the mini-split sits idle when not needed - and "wakes up" when temps drop below 40F or rise above 85F inside the garage. Or exceed specified "emergency" temperatures, regardless of schedule/user settings on the Nest (eg override "OFF" setting if temps drop below 35F).

The integration stuff was not cheap. However, the end result is not running heat 24/7 when it's above freezing outside, "warm enough" inside - or neglecting to turn it on when there's a cold snap. So pretty much feels like a win. Also nice to check remote Nest sensors from your phone when it gets into the low teens outside...