Recomendations needed for heater size

[ksarauer]

I'm in the process of redoing a pole barn, finishing off all interior walls with painted osb, r19 insulation bats, and blown insulation for the ceiling, somewhere around the r30 mark. Pole barn is 30x50 with 10ft ceiling, located slightly north of the twin cities in MN. Heat will likely be propane, and I'm planning on keeping the temp around 38-40 degrees, and bump it up to ~60 when working out there, ~ 6 hours, 3 days a week.

I'm planning on putting the heater, or heaters in the center on one of the 50ft walls. I was thinking 2 smaller heaters and point them at opposite corners to maintain more constant temp. Thoughts?

What size of heaters should I be looking at? Any types to stay away from, or recommended over another?

I should also add that ~1/3 of the space will be used for entertaining from time to time. If that makes a difference..

 

[grinch365]

It will depend a little on how many doors and windows and whether you have overhead doors that will be opened often or not. Bigger will allow for quicker heat up after doors opened.

My GUESS is one 80k btu heater would be enough. (from what I've gleaned from my research.) Two 40-50's would be better for more even heat distribution, I'm sure.

I've just installed a 125k hanging BIGMAXX heater in one end of my 40x56x13.5 pole barn here in Colorado. I'm at 7500 ft elevation though and from what I gather you have to derate the heater for altitude. so its closer to an 80-100k btu. I'm using propane and had a 330 gallon tank delivered and hooked up, but it hasn't been filled yet, so I can't tell you how its working yet.

 

[larry_g]

Whatca doin in there? Is it mostly storage? Woodwork? mechanics and fab work? Do you really need to heat the whole volume? I went with a divided and partially heated shop/storage. See below. I only heat the machine shop area and the rest is cold.

lg
no neat sig line

 

[ksarauer]

Whatca doin in there? Is it mostly storage? Woodwork? mechanics and fab work? Do you really need to heat the whole volume? I went with a divided and partially heated shop/storage. See below. I only heat the machine shop area and the rest is cold.

lg
no neat sig line

1/3 of it is going to be man cave/entertaining area with tv/bar etc... The rest will be used for a shop, repairing whatever is in season, sled, boat, jet skis, atv, auto, etc, along with any small projects going on whether it's wood working or metal fab, and as little storage as possible. Seems we always have at least 1 thing going on, generally 3 at a time, and I really don't like working in the cold.

 

[ksarauer]

It will depend a little on how many doors and windows and whether you have overhead doors that will be opened often or not. Bigger will allow for quicker heat up after doors opened.

My GUESS is one 80k btu heater would be enough. (from what I've gleaned from my research.) Two 40-50's would be better for more even heat distribution, I'm sure.

I've just installed a 125k hanging BIGMAXX heater in one end of my 40x56x13.5 pole barn here in Colorado. I'm at 7500 ft elevation though and from what I gather you have to derate the heater for altitude. so its closer to an 80-100k btu. I'm using propane and had a 330 gallon tank delivered and hooked up, but it hasn't been filled yet, so I can't tell you how its working yet.

no windows, 2 36" doors, 1 11wx9t overhead door. I'm leaning toward 2 75k-80k heaters, and I would stagger the temp on them, so they weren't both running at the same time. The price between 50k and 75k is minimal, and this would give me redundancy, along with faster recovery time when needed.

Not sure if were gonna have a 250gal or 500gal propane tank for these or not. I'd like to make the 250 work, simply because of the smaller footprint, but will likely end up with the 500, even though i don't see us using that much energy to heat it.

 

[finn]

Check with the manufacturer of your heater to determine if the heat exchanger is rated for use as freeze protection. Some, like my Beacon Morris, are not suitable for maintaining low temperatures in garages or warehouses, apparently because of concerns that condensation will corrode the heat exchanger. The user’s manual says to keep the thermostat to a minimum of 50 degrees to prevent condensation damage to the unit.

I think there are low temperature units available, with stainless / corrosion resistant heat exchangers, but they are more expensive.

 

[19D2P]

You need to do a Manual J calculation. Anything else is just a WAG that will cost you in the long and short term.

 

[bobj49f2]

I insulated my 30'x50' with 15' high ceiling this spring and installed a infrared gas fired tube heater from Re-Verber-Ray. After reading numerous post giving this company good reviews I called the local rep to get help in buying the proper heater for my application. The rep worked with the manufacturer to size the proper unit for my building. I sent them a drawing of my building with the size and placement of my doors and windows along with my insulation specs and they were able to do a heat loss study and recommend the proper sized heater. I got a 30' long (I built a 10' deep second floor mezzanine from the back wall) dual output 65K/100K BTU furnace. I run it on LP and had a 500 gallon tank installed. I am located just north of Milwaukee, WI. I just started the furnace the last week, the temps dropped down into the low 30s this week. it. I'm using my entire building as shop space for my business and other odd projects. I also have two ceiling fans to push the heat from the upper part of the shop. They make a big difference.