Heating and cooling shop?

[talvare]

Ted knows more about HVAC than I ever will. Ted, is my description of how heat pumps work reasonable, if maybe a little clunky?

You did good Bob.

My response to the OP was pretty vague, so I should be a little more specific. First let me say that I'm not familiar with your climate so I base my suggestions on the climate where I live, where temperatures generally range from low 30 deg F temps to over 100 deg F. My suggestion for using an 18KBTU unit is based on your shop being well insulated with finished walls and ceiling, standard 8-9 foot ceiling height, minimal glass, any roll-up doors well insulated, etc. If any of these conditions are marginal, I would step up to a 24KBTU system. If these conditions are non-existent, and the shop is constructed as many garages are with no insulation, no finished ceiling (open to the rafters), etc. and you intend to leave it this way, you should perform a heat load calculation to determine the size of unit required. These conditions will dramatically affect the required heating and cooling equipment.

Ted

 

[ddickey]

My Daikin has a dry mode. I don't think I've had to run it on AC. It keeps my 400sqft garage plenty cool and dry too.

 

[Bob Korves]

If these conditions are non-existent, and the shop is constructed as many garages are with no insulation, no finished ceiling (open to the rafters), etc. and you intend to leave it this way, you should perform a heat load calculation to determine the size of unit required. These conditions will dramatically affect the required heating and cooling equipment.

Well said, Ted. Having a shop that is not insulated only keeps you from getting sunburned and keeps the rain and snow off your machines. Well, it also helps to keep your tools from walking away... It does little to stop the heat flow, in both directions. My shop is not insulated at all, except for portions of two walls on the house side. It gets cold out there in winter, and I am thankful for this climate that rarely gets below 28F (-2C) in the winter. It does, however, get above 105F (41C) every summer, and regularly above 100F (38C). In the summer I only really work for more than 15 minutes at a time in my shop before noon. I am now looking for a new house to move to, and will try to end up with something that meets my hobby machining needs as I age, and also meets my new wife's demand for both our cars being kept in an enclosed garage. Edit: the cars don't need insulation .

 

[Firstgear]

1 ton mini split. (12,000 btu)
$1,385 diy installed. 20 X 20 shop.
My garage is fully insulated, it’s 100 outside and my whisper quiet ac unit has my shop to 76.
I love it!

Jeff. which manufacturer?

 

[Tozguy]

Bob, the unit being quoted are good for as low as -10 degrees F.......which where I live is plenty good enough.

Agreed. Our thermo pump provides heating with outside temps down to -12 deg C. Defrosting heat and auxiliary heat come from an oil furnace. When temps get above 23C in the house the cooling includes dehumidification and that is pure luxury around here. Thermo pumps are set and forget systems with negligible maintenance. Worth every penny they cost.

 

[MikeInOr]

I installed a 18000 btu Fujitsu myself. It has the top rated efficiency. It worked beautifully for about 6months then slowly started going down hill. Did I not evacuate the lines well enough? Are the lines leaking? Is the compressor dieing? Will a recharge fix the problem or do I to find someone with a freon leak detector?

One evening I had an inspiration... sure enough the filter was packed so tight with dust there was practically no air movement. Cleaned the filter and it is as good as new! --that was about 2 years ago.

Like you said every brand has bad reviews. I am really pleased with my Fujitsu and would have no qualms buying another and installing it myself!

 

[jschmidling]

Every cloud does seem to have a silver lining.

Before the shop burned down, a 10,000 BTU window unit mounted through the wall was good till around Noon. After that, it was uninhabitable.

After the rebuild, I put a 5000 BTU in two of the windows and have yet to have to turn on the second. I have yet to see it get above 73F in the shop and it runs only during the day.

The shop is 2400 sq ft, has 7 windows, white steel roof and tan vinyl siding and fully drywalled and insulated including about a foot of blown stuff on the ceiling. I can't say enough for the benefits of modern materials.

The original was the same footprint but no windows, wood siding, dark shingle roof, mostly dry walled but I know nothing abut the insulation quality.

New is nice,

js

 

[3strucking]

I have a 30 X 40 X 10 tall steel sided building in southern Michigan
1" foam side walls
2" ceiling insulation
.060 Aluminum sheet covers the entire inside
6" concrete floors
1 entry door two 10' sliding doors
(1) 10 X 10 utility room Heat- air compressor - electrical
it has (4) 250' 1/2" water lines runs in the floor
a 40 gallon natural gas water heater supplies the heat to the floor
at 80 Degree water temp in the winter the floor stays at 64 degrees that is with temps in the 0 to 5 degrees outside
in the summer with two fans on when I'm in the shop it stays at 75 degrees
installed an attic fan for summers heat but never used it
I keep the small door shut when it gets in the 90 degree days

That was well thought out and it shows by the temps.

 

[Mikkell]

Here in AZ I tried a Mini Split the said it would cool 900 sq ft. Ha, not even close. My shop is only 480 sq ft. After it crapped out a Guy on CL installed a regular AC unit, much better.

 

[Janderso]

Jeff. which manufacturer?

Mr Cool