Cooling my basement shop part 2. Or, learn me mini split air conditioning

So, with a few days comes a potentially bigger budget.

We'll call it 1500 max.

Im thinking that mini split air conditioning may be the better alternative in the ling run over a portable unit. It also has the benefit of heat in the winter, and potentially better resale value of the house down the road. Probably more energy efficient as well.

500 square foot basement shop, 3/4 dirt up the 12 foot high walls. Essentially all below grafe except for the wall with garage doors.

Id want ac, heat, and dehumidifier. As well as a unit that doesn't suck. Think long term life.

I have no idea what i dont know about this, who to look at, etc. Well above my pay grade here.

And go!

Bump for the morning crowd

I am in a similar position and like the idea of a mini split better than hacking into the ducting above the shop. I want to see what you end up with.

I'm looking at the same solution for my finished basement, here's the thread I started about it: https://grassrootsmotorsports.com/forum/off-topic-discussion/mini-split-ac-unit-for-basement-instead-of-runnings-ducts/129165/page1/

I had a mini-split installed in my finished attic and at certain times of the year it's the most comfortable room in the house. If you have the budget for the mini-split, go with it. The only maintenance I've had done is to clean the coils and wash the interior filters, it's been running like a champ for 5+ years. Now that I've bragged on it, it will probably take a dump next week...

What brands are you guys using with long term success?

How does it do dealing with humidity?

I have a Mitsubishi mini-split in my 600 sf addition/master bedroom suite and it's been running flawlessly since 2010, costing very little to operate, even here in humid mid atlantic region weather. If I could I'd replace the standard central air in the main house with a set of mini-splits.

I've only installed one.

That said Daikin and Mitsubishi both have good units from what I've heard.

What about gree? Apparently they make the unit for trane, and i can get the whole 18k unit for under a grand.

Never heard of them before but short of unavoidable things like a factory leak in the coil or something breaking because of transit a new unit is generally going to work well so long as it's installed right.

I say generally because some companies suck but Trane isn't one of them.

Are you getting someone to install it or doing it yourself?

E: also, make sure the unit you're getting has a heat pump if you're expecting heat in the winter. Some of them are ac only.

Has a heat portion as well as dehumidifier ability.

Ill be doing it myself, as i cant afford the unit and rhe install. Friends with plumbers and electricians, so othe than vacuuming and purging the system, wr should be able to do it all in house.

You'll need a torque wrench with the right heads for the flare fittings.

So a 3/4 and 3/8.

I will say go slow with it, everything is tight inside and it's a bit of a pain in the ass.

Can you explain the torque wrench with heads for flare fittings please? Never heard of such a thing.

It's that. Both of the flare fittings where the lineset is connected to the indoor and outdoor need torqued down to different lbs. Off the top of my head it's 15 for the little line and 25 for the big but I could totally be pulling that out of my ass/memory. If it's a box deal and not a secondhand one the instructions will let you know the right amount.

Next stupid question:

Will my harbor freight vacuum pump and gauges work for home ac? I know its 410a vs 134a....

If the gauges don't have 410 on them you wont get the right readings and might over charge it.

Other than that if it's the can crap it's got sealants and E36 M3 in it that I wouldn't want to send into the system. Far as I know a vacuum pump is a vacuum pump so that should be fine.

I've installed three Klimaire units and a Harbor Point. All 4 units are still in service, with the oldest being right at 12 years old. Three are R410, one was R22 and is now running on propane. Only the Harbor Point needed warranty work, and the manufacturer supplied me the parts with no questions asked. One of the Klimaire units did need a drive board after a lightning strike. The unit was out of warranty, but Klimaire sold us the parts needed with no issues.

Your HF vacuum pump will work fine. You will need an adapter to hook up to the unit. Whoever you buy the unit from should have them.

Most units come pre-charged for 15 feet of lines. As long as you use 15' lines you really don't need a gauge set. Then, the only hose you need off of your gauge set, is the yellow hose with the adapter on one end. Hook up the pump and let it run for 30-40 minutes. Turn a couple of valves and you are done.

I have not used a torque wrench on any of my installs. I checked all the connections with soapy water after the lines are charges. No leaks yet, but to do it right, you should probably follow the directions.

If I was going to buy another unit today, I'd buy a Klimaire. I've had very good luck with their products. Their stuff runs well and the units are extremely quiet inside and out. They have some variable speed units that have seer ratings in the mid 20s. That's pretty hard to beat.

You will also need a condensate pump if the evaporator core is below ground level. Unless you can drain it out of the doors or into a sump.

That's all I can think of at the moment.

Condensate pump is part of the puzzle that i was missing. Didn't know that was a thing, but a big solution to the problem of draining from below grade without adding a 6 mile strech of pvc.....

Do you know if you cam get them precharged for a 25 foit lineset?

I also need to do some research on how to adjust torque values for a normal torque wrench and crowa foot. Cant justify the expense of a special tool for one time use.

In reply to Toyman01:

We've had decent luck with the M099 replacement in 22 units. It's like a quarter of the cost right now and seems to cool better than 22 did.

In reply to Dusterbd13:

To my knowledge, they don't come charged for 25' lines. R410 charges as a liquid rather than a gas, to keep the blend from separating. That might make DIY a little tricky but I figure I'm at least as smart as a HVAC tech. Worst case, you have to call a HVAC company to top it off.

They make condensate pumps that hang right below the unit, so the condensate line can be run with the refrigerant lines.

In reply to Toyman01:

Awsome.

Any recommendation on placement of the inside unit?

Would there be any issues with mounting the outdoor part on the wall outside above the garage door?

Klimaire has a 115 volt 12k btu system that seems like it will do the job perfectly. Indoor side mounted on the wall between the doors on the south facing wall, outside on the wall.

Thoughts?

They make wall brackets for mounting the condenser unit to the wall. That is very common in other parts of the world. Apartment complexes will have them mounted outside windows all the way up the building. Klimaire should have them in stock.

For the evaporator, higher on the wall is supposed to work better than lower on the wall, so mounting it above the door should work fine. IIRC, they want at least 8" clear above the unit.

Fair warning, the condenser unit is fairly heavy. It's going to take some strong help to get it up onto the brackets.

Cool. Ill have to measure the space. I beam may prevent a clear 8 inch span.

What about the units relative height? Equal height ok? Or does one need to be higher?