overhead heater for new shop

[conan]

I'm putting up a 2400sq ft shop and I'm wondering how many btu overhead furnace I would need. The shop will be fully insulated and I don't need it tropical in there. I've ruled out radiant heaters.

thanks in advance

[coreya3212]

Originally Posted by conan

I'm putting up a 2400sq ft shop and I'm wondering how many btu overhead furnace I would need. The shop will be fully insulated and I don't need it tropical in there. I've ruled out radiant heaters.

thanks in advance

Volume counts. How high is the ceiling? Why have you ruled out radiant heaters?

[2011laramie]

Rough rule ive read is 40-50 btu/sq ft.

So that equals roughly 100000btu. Add efficiency loss, id shoot for a 120000btu/hr unit.

But a proper heat loss calc would yield a more precise answer.

[Don K]

Put in something larger than you need... Go with a Reznor 150,000 or equivalent. There's honestly next to no difference on the price of the heater when going from a 100-125k or 125-150k. You'll be happy that you can get a quicker recovery when you are trying to warm it up or reheat it on a cold day. It will basically burn the same amount of gas to heat the building, just quicker.

[t.tinsmith]

Low intensity infra red tube heaters are the most economical to operate. A heat loss calc is a must to size the unit. Bigger is seldom better when this is done. These tube heaters don't require a band of temp rise to run well and you can operate them in any low temperature if you like without damaging them
Good luck

[conan]

I will have 14 ft ceilings. I'm going to store a travel trailer in there and I thought radiant heater would get the trailer to warm

[Blastoff]

Put your trailer on the other wall. I second the radiant heater more efficient than over head or boiler

[conan]

Originally Posted by Blastoff

Put your trailer on the other wall. I second the radiant heater more efficient than over head or boiler

Are the radiant s rated the same way in btu?

[Blastoff]

Originally Posted by conan

Are the radiant s rated the same way in btu?

I believe they are, but I am not a furnace guy.

[Blastoff]

Some one will chime in, but there is a distance vehicles should be parked away from the radiant tubes. Also the RV height should be around 11 feet high and if you leave room you will be fine.

[Knot Rite]

I had a Hot Dawg installed in my newly built man cave garage. Things got changed and the heater ended up near the t.v. Well that sucks.
Not sure how many BTU's it is but it can heat up B.U.T the size of a T.U.B.

Bobby

[skidderman]

I have the radiant heat and wish I had not done it.

[Stubb]

Also makes a difference on whether you are using spray foam insulation and leaving your trusses exposed or are you going to have a ceiling. If you have a ceiling and good r value id say you need a 150,000 unit. if you have the exposed roof and spray, you might need two 150's. I just finished a 1500 sq ft shop with 12' walls, insulated very well and went with one 125,000 BTU Reznor.

[conan]

Originally Posted by skidderman

I have the radiant heat and wish I had not done it.

Why is that skidder?

[bat119]

I worked in a sheet metal shop with radiant heaters I didn't like the heat directly on me all the time sort of like working in the sun. Our shop had a 24' ceiling you could still feel heat when they came on, the worst was a heater directly over the shear and brake, we built a sheet metal umbrella for a shield.

[Smokinyotes]

My shop is 2400 sq ftand i have a 150,000 btu tube heater works great

[skidderman]

Originally Posted by conan

Why is that skidder?

Too much heat focused in one area. Front of garage hot, back is cold. Can't leave my truck in because heater heats front of truck too much. A forced air would be more consistent and no concentrated heat. If my garage was higher I guess it might be better but not much. From my perspective it was a big mistake.

[liar]

Originally Posted by skidderman

Too much heat focused in one area. Front of garage hot, back is cold. Can't leave my truck in because heater heats front of truck too much. A forced air would be more consistent and no concentrated heat. If my garage was higher I guess it might be better but not much. From my perspective it was a big mistake.

my last garage had underslab heat and this one has overhead radiant . i am more than happy with the radiant heater . when i was shopping for it i talked to a lot of people and was told that a common mistake made is too big a heater ( industrial ) for too small a building ( residential )

[skidderman]

Originally Posted by liar

my last garage had underslab heat and this one has overhead radiant . i am more than happy with the radiant heater . when i was shopping for it i talked to a lot of people and was told that a common mistake made is too big a heater ( industrial ) for too small a building ( residential )

I could have too big a heater. I sized it according to charts but who knows. The other thing I could do is change the angle so it shoots further out. I may give that a try next fall.

[liar]

mine is a " calcana " . google it if you want . its been 5 winters and no issuses so far .

[Kale 19]

We built a 42'x60'x16' shop a few years back and installed 2, 75000 radiant heaters. Buddies of mine are gas fitters and we checked the specs and 1, 75000btu heater was enough for that shop. The shop is insulated with r25 in the walls and r60 in the ceiling and one heater is more than enough to keep it at 10C through the winter even on the coldest days. I installed the pair in the event one goes gown I have a backup. One gets set to 10C and the other at 8C. I do alternate from time to time to blow out any condensation. Remember that once your slab warms up, it will retain a lot of heat as well and help with recharge time. Only downside to the radiant tubes is that you will want to keep distance between them and your RV, at least 4-5ft.
We keep 2 fans running on low all the time and the shop stays at a very consistent temp. It was a bit more money to install 2 but when I'm away, I know the shop will (or should) always have a heat source. The peace of mind was worth the extra dough.
In floor would have been my first choice but at 20k more, I opted for the tubes and am very happy with them.

[FISHBATTEREDBEER]

Watch for big sales at Princess auto this time of yr on overhead units,I bought a Mr. Heater 80,000btu for just over $400 a few yrs ago,over 50% off.