Hydronic heat source for 16x26 garage

[ChadB]

I'm in the process of building a 16x26 garage on a thickened edge floating slab, at my cabin in Northern MN. I have 2 inch F250 under slab and 2 " F150 around perimeter. Tubing is 1/2" barrier Pex 12" OC, 2 loops @210 ft each. Walls will be 2x6 R19, 9' ceiling R38. I am told I need around 10000 BTU output heat source (which may be low). Wondering what would be the best heat source for this application. I have 230V 40 amps available (also for lites and outlets), but will put in a Propane tank if needed. I will be storing ATVs and other gasoline vehicles in the garage, so flames concern me as well. Your comments and experiences are appreciated!

 

[HoosierBuddy]

This is one of those "how much do you want to spend?" questions.

If 10,000 BTU is right...then theoretically an electric water heater, rated at 4500 Watts (15,300 BTU/Hour) would heat your garage. However, that seems way too low to me. Did you consider the overhead doors in your heat load calculations?

If it runs constantly for a month, and your power costs are say...10-cents/kwh...your maximum power bill would be $324.00 That's 24 X 7 for 30 days if the water heater never caught up. You should probably check your power cost/KWH vs what you can get propane for before you decide.

Phil

 

[ChadB]

Here's some more info. The heat loss calculation of 10,000 BTUs was provided by my radiant tubing supplier (NIBCO). I just found a online calculator from H-Mac, a Modine dealer, and it shows 10,064 BTUs, or 2949 watts for a temperature rise of 72 degrees, so it looks like that's about where were at. I will keep the stat at 50, and bump it to 60 on the weekends. There will be 1- 9x7 overhead door. Electric rates are around .08/kwh.
Thanks, Chad

 

[G M]

This is the boiler I have for my system, it is electric

http://www.conceptmfginc.com

 

[medic583]

Heh G M... why did you go with the electric one... aren't costs pretty high in this neck of the woods?

 

[G M]

No, actually I think our elec rates are among the lowest in North America. We sell power to the States and other Provinces. But that wasn't really the deciding factor. Efficency, versatilty of boiler placement, not having to dig a 100' trench, the cost of the gas line and the unknown cost of gas prices in the future is what sold me.