Placement for Hot Dawg heater

[westbrooklawn]

I've ordered a 60,000 btu hot dawg heater for my 28x36 insulated metal workshop (2 insulated overhead doors, 1 walk in door). The unit will be suspended from ceiling at about 8', but I can't find any recomendations for most efficient placement of the unit, ie. middle of short wall, middle of long wall, in a corner at an angle, etc. Does it matter? It seems that one position might provide better circulation vs. another position. Just looking for recomendations from someone who may have dealt with this issue previously.

 

[mikester]

I have a Hot Dawg in my 22x30 and I mounted it in the middle of a short wall about 18" away from the wall. The fresh air pipe went straight out the side and the exhaust goes up throught the roof about 3' from the ridge line. Im curious, what made you go with such a large heater ? My garage is insulated on all walls, ceiling, 2 9' insulated doors and 1 man door and I used the 45K BTU and I think I bought too big of a heater. I usually leave the thermostat at 60 and it roasts me when Im working out there.

 

[Absea]

I have a Hot Dawg in my 22x30 and I mounted it in the middle of a short wall about 18" away from the wall. The fresh air pipe went straight out the side and the exhaust goes up throught the roof about 3' from the ridge line. Im curious, what made you go with such a large heater ? My garage is insulated on all walls, ceiling, 2 9' insulated doors and 1 man door and I used the 45K BTU and I think I bought too big of a heater. I usually leave the thermostat at 60 and it roasts me when Im working out there.

Really? I have a 30x40x10 pole barn with osb interior walls and six inches of blown in in the walls, steel siding ceiling with 10" blown in. I have two 10x8 and one 9x8 insulated doors. I was planning on a HD75 60,000 BTU Hot Dawg heater. Do you think that is too much?

 

[mikester]

Youre kidding right ? Your garage is almost twice the size of mine. Also I have an 8' ceiling. I think theres enough HVAC guys on this site to give info on BTU requirements. Plus all the other variables like window sizes, the area around your garage (open fields or trees for a windbreak) make a big difference from what Ive been told. I can say that my garage is about 20' from my house and I now have a row of 10' leyland cypress on the north side about 30' away. Last year I had the heat cranked up because I painted a lot of parts for my car. I kept the heat around 70 at least 3 or 4 days a week. I think it cost me more to heat the garage last winter than it did to heat the house.

 

[Absea]

Youre kidding right ? Your garage is almost twice the size of mine. Also I have an 8' ceiling. I think theres enough HVAC guys on this site to give info on BTU requirements. Plus all the other variables like window sizes, the area around your garage (open fields or trees for a windbreak) make a big difference from what Ive been told. I can say that my garage is about 20' from my house and I now have a row of 10' leyland cypress on the north side about 30' away. Last year I had the heat cranked up because I painted a lot of parts for my car. I kept the heat around 70 at least 3 or 4 days a week. I think it cost me more to heat the garage last winter than it did to heat the house.

You asked Westbrooklawn why such a big heater and his garage is close to the size of mine. 28x36 insulated metal workshop I was surprised that you thought it was too much heater for him and thought maybe you had some insight for me.

 

[mikester]

I do think the heater will be too big. I think the HD45 would be the better size but thats just my opinion. Like I said there are plenty of HVAC guys on this site that could probably give you good info on choosing the right size for your garage.

 

[westbrooklawn]

I did a lot of internet searching for information on garage heaters before I actually ordered one. Several online Hot Dawg sellers had btu calculators on their sites, and based on those, I thought I needed an HD75. You have to realize that while my metal shop is fully insulated, it is only insulated with reflective foil type insulation (thin, similar to bubble wrap with white on the inside, and foil facing towards the outside walls). I'm not sure what the "R" value of this is, but it is low. I finally spoke to a live person at this site: www.shophmac.com

I don't have the gentleman's name, but he was extremely knowledgeable... based on my input, and their sizing program, he felt the HD60 was the proper size for my application... I ended up buying from them ($586 delivered)... in addition to their excellent advice, they were also the lowest price I had found. I would highly recommend contacting this company for advice on sizing.

 

[bd8134]

I had an uninsulated 20 x 24, 10 ft ceilings, leaky doors etc with a Sterling 45k and that was ok. You could not have gone smaller. Mounted diagonal across the garage above my work bench but heat flow was very irregular. I mounted a box fan near the ceiling and then used a floor mounted oscillating fan to move the heat around. The thermostat was on an opposite wall and would still trip while another corner was still cold.
I now have a foam filled, 32 x 44 with R30 in the 12 ft ceiling, R16 garage doors, epoxy floor, with the same 45k heater, I hope it will be sufficent. It is not got that cold yet, maybe 35F but it seems a lot warmer and the heater does not run much, maybe an effect of the radiated heat / cold compared to my old walls. The garage temp has not dropped below ~50F even after the doors have been open.
I would recommend placing the fan diagonal, running fans if necessary or using the heater fan to run continuously after the heat shuts off, most can be set up to do this.
It is important to size the heater for the space. Too small and it will run continuously, too big and it will just keep cycling.
Just my opinion.