Looking for words of wisdom on an AC/heating unit for my new shop build.  I won't be heating/cooling the entire shop, but will be framing in a 10x30 portion for man cave/reloading room/dog house.  Anyone have any recommendations for such a unit?  I've seen the window units, as well as the "motel" type ac/heating units.  I'll be framing it in on the east side to cut down on sun/heat.  suggestions?  Here's what a crew of 5 messicans did in 6hrs yesterday...

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I'd look at the hotel type heat/ac

I'd also install on the hot side, I know from my window ac's it cools the room better from the hot side than from the cold side.

also if you're going to build it into the wall, make sure you get a through wall unit, it's different than a window unit and works better.

I've also looked at these a little zoned

The CORRECT answer is a ductless mini split. Extremely efficient, affordable, and if you buy a Mr Cool DIY, the linesets are precharged. All you do is plug everything in after drilling a 3" hole for the lineset to the evaporator on the wall, and yer done.

Assuming you want something For 10x30, an 18k btu unit which will do heat and a/c will do fine, and costs $1,457.

http://ingramswaterandair.com/mrcool-seer-ductless-minisplit-heat-pump-wifi-p-22614.html

There are several size choices but for a 10x30, a 1.5 ton should be fine.

For that large an area even if it is not partitioned use at least two heads.

If you will partition part of the area off (say for a separate finishing area) definitely two heads.

A 'big ass fan' can also help move the air around larger areas.

Buy a daikin and get it done professionally.

For 300 SF you will want a small minisplit with one head.

I'm not sure what the posters above are talking about.

That's what most of the posters are talking about. There are numerous brands.

Daikin or Mitsubishi and have it installed by a dealer from their listed dealers.

Doing so will get you a 10 year warranty on parts

Mini split is the way to go. Just remember that you get what you pay for.

If you want to self install I would recommend a PTAC unit.  Low up front cost but higher operating cost.  Just be careful to read the specs for actual performance.

If you have the extra money to throw at it a quality mini-split can be a nice option.  Operating cost will be substantially cheaper if you run it frequently or 24/7 and select a good unit. It's best to hire a HVAC contractor for these units.

Do you plan insulate the space well and have some type of wall / ceiling covering on the interior?

Small means 9,000 BTU or less.

Outdoor unit or all parts?  To get a 10 year warranty on all parts does that cost additional like an insurance policy?

<<< Not a HVAC contractor... just had a lot of exposure as a GC.

You're thinking run time, keep your powder dry?

Only if you can get the head very close to the middle.


A 30 ft dimension is getting a little large for the fans in most of those heads to adequately circulate.

2 7000btu evaps will be fine equally divided out on the long wall.
long side wall.  divide the room in 3 equal parts, and center the evap on the wall in sections 1 and the other evap in section 3.
30ft - width of each unit(around 30"  each) = 300 inches. divide by 3.  8'4".  measure off one side wall 8'4", thats the edge of the evap and do the same for the other side.

 youll have equal cooling, heating, airflow, and temps. thats how id do it. and when you dont need 2 evaps on, shut one off, but if its hot out, turn 2 on.

get a multi split unit, ton and a half 2 zone condenser will be fine if you use 2 7000btu evaps.

insulate it well.  if you do a shit job insulating, if not use no insulation, youll need more BTU's. insulate ceiling and walls.

Both Daikin and Mitsubishi offer 10 year warranty on all parts for the whole system. Only if you use a 3D (Daikin) or Diamond dealer(Mitsubishi)

I think both can be upgraded to 12 or 15 years for additional cost. I know Daikin can

Yes...  It will be 10ft wide and 30ft long..  I would prefer to have the unit all on the east side wall.  The space will be framed,  8ft ceiling installed with decking and well insulated.  Is this feasible?  I realize its a long area, but (i consider) a relatively small space.

Your right, it is a small space, similar to a economy motel room. PTACs are functional but not as elaborate as what someone may prefer at the house.  The guys above are mentioning multiple units to condition the space equally and to move all of the air in the space.  If you only have one unit there is going to be dead air space at the far end of the room.  The space will eventually balance within a few degrees but it's slower process.

I'll try to keep this short.  We built an addition on the back of our office for a company meeting room and a pool table.  It was larger than your space, roughly 22 x 35.  We used a PTAC because it was the only room in the building that someone could smoke so we didn't want to share duct with the existing building.  We didn't use the space every day so the PTAC was often turned off.  If we had a planned meeting ( summer, 95 degrees out ) the office staff would turn the unit on in the morning and it felt good in the space at noon and the indoor humidity wasn't bad.  Setting the fan on high helps to throw the air across the room but you get more noise.  I say that making the assumption that you won't run the unit 24/7.

Thanks!  I don't know why I was thinking 7 years for a Diamond dealer.

Since its a workshop and not a living space, I wouldn't hesitate to just use one mini split. It might not be totally evenly cooled but that's not critical in a workshop. A fan would also help move the air around.

I'd probably get a 9000btu unit and mount it on one of the 10 ft ends. You could get a Pioneer or Blue Ridge system for about $550-700.

No it's not a perfect system but then it doesn't need to be.  If you don't insulate all the walls very well, then you might want to upgrade to a 12k btu but with all walls insulated to the standard or above for your area, a 9k should handle it.

I wouldn't do it this way if it was a residence....but then most people don't build 10x30 residences.

Bear in mind, this will be marginal for winter heating in OK. On very cold days you probably will have to supplement with something else. I like vented propane or natural gas. But, if you only needed supplemental heat occasionally you might be able to get a 240volt electric heater and only use when absolutely necessary. They are cheap to buy and install but expensive to run depending on your electrical rates.

It used to be 5 years on parts and 7 years on the compressor. But both companies up the ante to 10years on parts and couple extra years for additional cost

Thanks guys!  I'm leaning towards the mini split, probably more towards the 12K sized unit.  The efficiency of the units appeal to me.  Funny, I've seen these all over mexico and Asia, but never really thought much about it...  Just thought it was a "customary" type unit for whatever country I was in... (obviously i know little to nothing about HVAC...)  I will most likely be a weekend warrior, and can fire it up Friday evenings.  I'm not opposed to a small fan stand running or oil filled heater to help take up the slack.  Thanks for all the insight, and appreciate the feedback Billhw1!

Op- take a look at Daikin and Mitsubishi if you don't mind more cost for longevity and heating performance.  HSPF is something you probably want to research, "heating season performance factor"...  Above 10 is good for a heat pump.

If you read this link, click manuals then submittal, you'll see that the Mitsubishi H2I / hyper heating units provides very good heat down to 5 degrees. LINK  That's one of the reasons why ColtRifle mention you may need to supplement during the heating season for less expensive mini-splits.  Performance for economical systems starts to fall of at 40 degrees + or -.  In Florida or Texas it's not a big deal, further North it's on a sliding scale.  Or you add a oil filled heater during the extreme temps.

Good luck with your project, I need a man cave too.