Shop Heater Location???

[Steve Goetz]

After some consideration and questioning from you fine folks here at SMC, I've decided to add a 80K BTU Mr. Heater forced air unit in my garage/workshop. It is roughly 30 x 36 with 9"+ walls. There are 2 OH doors in the front (9x7) and one in the back right rear. No windows and the exterior walls are 5-1/2" logs. There is also a stairwell that leads to the second story on the right side near the door that leads into the house and another man door on the front right corner. My gas feed is located on the left side of the garage near the rear where I want to make my connection, but can route it just about anywhere. My question is, where would be the best location and direction to put this unit to get the best airflow and heat circulation? I also have plumbing that feeds a half bath on the right side, underneath the stairs that I need to keep from freezing as well. My thought is near the gas connection on the long wall pointed towards the front of garage to get a circular flow, but I wondering if their is a better location. TIA

(P.S.- I will try to add a drawing of my garage later today when I get time to draw it up)

~Steve

[Jim Becker]

You need to add venting to the equation for that unit...that has to go out a wall or up to the roof and also use specified materials. Be sure you keep that in mind since there are some distance/direction parameters involved with venting that must be adhered to for safe operation.

[Bill Dufour]

Is that a through the wall or ceiling unit. regardless mount it so there is easy access from the ground with machinates in normal placement. My shop attic has a hatch right above my 650 pound tablesaw that has to be moved to get up there.
Bil lD

[Ron Selzer]

Back left side where the gas is, pointed towards front garage doors, angled at 30degrees off of the left wall

put the tstat on the front wall between the garage doors (put at least a 1" thick piece of foam insulation behind tstat so the cold doesn't travel thru the wall)
OR
put the tstat in the bathroom)

good luck
Ron

[Steve Goetz]

Ron, that is where I had initially thought about locating it....easy access to the gas line, and venting will be horizontal, thru the wall. My question is thermostat placement...wouldn't it be prudent to put it under the heater to get a reading where the heat circulates back around to to heater?

~Steve

[Jim Becker]

Ron, that is where I had initially thought about locating it....easy access to the gas line, and venting will be horizontal, thru the wall. My question is thermostat placement...wouldn't it be prudent to put it under the heater to get a reading where the heat circulates back around to to heater?

~Steve

I'd put the thermostat on a different wall at normal wall height for the same. Pick a location that requires the heat to circulate out to, not just top to bottom. Sometimes a small, quiet fan somewhere in the space can help with these kinds of wall/ceiling mounted units have better circulation and even heating.

[Ron Selzer]

Ron, that is where I had initially thought about locating it....easy access to the gas line, and venting will be horizontal, thru the wall. My question is thermostat placement...wouldn't it be prudent to put it under the heater to get a reading where the heat circulates back around to to heater?

~Steve

Based on your earlier comments the most critical item to protect is plumbing lines. Therefore set the t-stat close to those lines and see how the rest of the area goes.
Under the heater may work fine and may not all depends on how air flow moves in this area, how far the heater throws air out, how many drafts (size matters) are letting cold air in, etc

Main thing is decide what area of this space is most important/critical to maintain a given temperature and that is where you want the t-stat at. Depending on are you trying to keep all of this space 60-70 degf or just keep the water lines from freezing or one spot in the area needs to be 72 degf and the rest above freezing. Once you figure out what is important to you then you will know where to place the t-stat. Remember t-stat wire is cheap, buy enough to go to the farthest point and then move the t-stat to different locations until you get the combination that works for your needs
good luck
Ron

[Jack Frederick]

If you put the stat under or close to the unit, especially with a single stage burner that thing will short cycle to the point of driving you nuts and not heating very well. 80k btu is a lot for >1000 sq ft. That will cause it to cycle as well. You will have better comfort and efficiency with a smaller unit. What is the worst that will happen? When it is -10 the heater will run all the time and you may be slightly cooler in the space, but not that much. You are at those deep cold temps (design condition) less than 3% of your seasonal heating hours.

[Steve Goetz]

Agreed, thanks Ron for the advise....will likely try and put it near the plumbing to ensure that area stays well above freezing. Thank you all for the suggestions/comments. Much appreciated!

~Steve