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Maker of Fine Sawdust
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How big of an AC unit do I need to cool a space that is 25' x 50' and, here's the clincher, 25' tall:eek: . It is a warehouse style garage bay that is now my cabinet shop. Granted, only the bottom 6' needs to be kept cool (for me of course), but I'm not sure how it would work because of the height of the building. BTU or tons would work for me. Thanks.

Leo
 

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DGR,IABD
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Need more info... # and size of windows. R value of walls and roof. Size of overhead doors and type of overhead door. # of occupants. type, #, and wattage of lighting. Color of roof. type of roof and outdoor siding material. Any processes conducted in this building that generate heat (heat treating, welding, cooking, etc.) Zip code you live in.

There's a hell of a lot goes into a full Manual 'J' calculation.

If I had to take a wild somewhat educated guess, I'd come in around 6-1/2 to 7 tons.
 

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Maker of Fine Sawdust
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Discussion Starter · #3 · (Edited)
mdshunk said:
Need more info... # and size of windows. R value of walls and roof. Size of overhead doors and type of overhead door. # of occupants. type, #, and wattage of lighting. Color of roof. type of roof and outdoor siding material. Any processes conducted in this building that generate heat (heat treating, welding, cooking, etc.) Zip code you live in.

There's a hell of a lot goes into a full Manual 'J' calculation.

If I had to take a wild somewhat educated guess, I'd come in around 6-1/2 to 7 tons.
# and size of windows.
None in the area that need conditioning.

R value of walls and roof.
R 13-15?.

Size of overhead doors and type of overhead door.
12'w x 14't steel, insulated, 3 windows 8" x 15".

# of occupants.
Me, 1.

#, and wattage of lighting.
2 double tube 75w 8' fluorescent 12' off ground, 2 70W(?) Low pressure Sodium (orange light) ceiling level.

Color of roof. type of roof
White/silver, corrugated steel.

outdoor siding material.
Dark Green, corrugated steel.

Any processes conducted in this building that generate heat.
Sawdust vacuum system.

06096


So MD, have you been assigned to answer all of my questions? LOL. Thanks.
 

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DGR,IABD
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Leo G said:
So MD, have you been assigned to answer all of my questions? LOL. Thanks.

No, I'm just a fat-headed know it all. :cheesygri

I was just asking a few preliminary questions that are necessary to do the manual J calculation. I'm sure one of the HVAC regulars have the software to pop all this into. I'd have to do it long hand, with the manual J forms. If nobody responds in a day or two, I'll do the calcs long hand for you. No biggie.
 

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:cheesygri well are you looking in to buying a window unite,, or are you hooking it up to your furnace and runing duct work? that also helps for the calc. if on a furnace, i wiould recomend a 2 ton unite, one question .. were do you live that also make a very little difference. :D
 

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Norm abraham (new yankee workshop) has in his work shop one of those duckless central air units. He said its whisper quite and does a exellent job. Doc knows what i'm talking about. I think hitachi makes them and ANOTHER manuf. also maybe.
 

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Yup. We use the Mitsubishi Line of the called Mr. Slim. Work great and you can add multiple blower units on one condenser.
 

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HVAC Doc said:
Yup. We use the Mitsubishi Line of the called Mr. Slim. Work great and you can add multiple blower units on one condenser.
yep :Thumbs: Its mitsubishi I new it was a asian company thats it . :cheesygri
 

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For this kind of space, open bay workshop, hangar, etc, your best bet is to get a Space Ray gas-fired radiant heater for your winter heat (especially in CT), and use an exhaust fan in summer.
Any time you have in filtration of 1 air change per hour, you sould go with radiant heat.
 
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