Shop/garage heating & cooling: what'd you go with?

[Charley Lillard]

My car barn is 50'x100'. I started out just wanting heat to keep moisture away in the winter. The cost of radiant heat was too high so I decided to do a gas furnace. Alot of the cost is in the ducting etc so for a little bit more I just went with a combo heat/ac unit. I put in a 5 ton unit. In the summer it would run the ac all day and still not cool it so I added a second 5 ton unit. I have the building sealed up pretty tight with a outside air intake that filters the outside air. The fan is always on low and pulling just enough outside air in to pressurize the building to keep the dirt out.

[Chevy454]

Clill: ours is almost the same size, 60x100...is your ac/heat unit overhead, or standard fare house furnace? I see your ducting overhead, which is basically what *I* have in mind...but when we've asked some local "contractors", some say waste oil, some say propane overhead, yada yada...I'm doing a ground source system just across the field for our new house, and I was originally gonna tie the 2 places together and share part of the lines since we have to have so many hundred feet of them anyway, but noone here seemed to have a clue if it was possible or not...?

[Charley Lillard]

Mine are standard ground units with Propane for the heat.

[RS69]

For a 60x100 you'll need 12 tons. thats 500 sq.ft. a ton. if your doing ground source in the house, while the contractors there drilling the wells go ahead and have him drill wells for the garage. one well for each ton. when installing the ductwork, if you supply up high, the return should be low, and visversa. be carefull if you bring in oa to the system, so as you don't bring in to much. to much will cause humidity problems if the equipment is not sized to over come it. (i'm a mechanical eng. and design hvac systems by day and work on cars by night.) hope this helps

[JChlupsa]

Can someone explain the concept of heaters

[rsatz28]

[ QUOTE ]
For a 60x100 you'll need 12 tons. thats 500 sq.ft. a ton. if your doing ground source in the house, while the contractors there drilling the wells go ahead and have him drill wells for the garage. one well for each ton. when installing the ductwork, if you supply up high, the return should be low, and visversa. be carefull if you bring in oa to the system, so as you don't bring in to much. to much will cause humidity problems if the equipment is not sized to over come it.

[/ QUOTE ]

While the initial cost may be a bit more, you may want to install two smaller units (that add up to 12 tons) so that they can be staged for better humidity and temerature control. I do not think you can get a 12 ton single phase unit, but would have to go with a 3-phase unit.


An oversized unit will short cycle the unit (esp the compressor in AC mode) to death. Aslo, the "noise" factor may be an issue.

Electrical costs may be lower running lower HP blowers, compressors and condesner fan motors.

Keep in mind that you will only need max heating and cooling a samll portion of the year.

[CanadianPoncho]

I run a Schwank 20ft radiant in my 20X32 garage. It is spray foam insulated as well. Very, very air tight! I have to crack my garage door open a touch when I turn my ventilation fan on. Overall I'm happy with it. It gets very warm very fast!
Todd

[Chevy454]

We ended up going with a heat pump...so far, so good!

[P.J.]

I pondered all those options too.Then a friend of mine said
why spend all that money on a heating system for my 20 x30 insulated shop.Just go to HOME Depo and buy a 220 volt
electric thermostat fanned heater for $ 75.00 and that all you need.
I Did just that and its perfect I can control the temp
as hot as I want. When I go to work in the shop I turn it on and in about 10 minutes its at 72and hotter if I want.
I also leave the heater on at about 55 when i am not working in the shop. The electric bill is just slightly more than when I am not running it. My friend put in a gas
overhead furnace at a cost of 1500. dollars. It will take a long time for me to spend 1500. on electric bill to heat my shop
PJ