Shop heater -- I'd been doing it wrong all these years

[ChuckM]

My shop (2-car garage) is about 22' x 20', equipped with a 240V / 250 cfm garage heater rated 4800 W (or 16,000 BTU). According to these guidelines, it should be good enough:https://homeguides.sfgate.com/figure-btus-electric-heater-73701.html

I never felt it that way because my heater turned itself off, after running 15 minutes or so, and then restarted after the temperature fell down a bit (after another 15 mins?). So my shop was never warm enough, and I have a couple of radiant heaters to help.

[attachimg=1]

It hit me when I saw a comment about the importance of placing the heater I have at the right height. Of course, the heater shut itself off because hot air rises, and the heater's sensor kept cutting its power off after running for 20 minutes or so!

After placing the heater on the ground, I found the heater going non-stop during the hour I was there!

[attachimg=2]

I must have been misguided by this image that I saw long time ago, thinking that a garage heater should be mounted close to the ceiling, How dumb.

[attachimg=3]

 

[luvmytoolz]

That's one reason why I've always hated those bathroom ceiling heaters that double as a fan. Literally sucking up cold air past the heater, has to be the most inefficient design ever?

 

[semenza]

I think the reason shop heaters end up near the ceiling is to preserve floor space and keep them away from things that might burn.

Seth

 

[rhoyer]

Is there no way to run a remote thermostat? It can be wherever you want it as long as it’s checking the temperature where you want it warm.

 

[Vondawg]

Yes good idea…I’ve seen it done
But maybe it works for you to have the heat circulating low and rising upwards

 

[Crazyraceguy]

Is there no way to run a remote thermostat? It can be wherever you want it as long as it’s checking the temperature where you want it warm.

This is exactly it. On those "self contained" units, it can only be regulated by the air it draws through itself.
Heater up high, thermostat up high, warm air up high.
If you relocated the thermostat down to where you are, problem solved, you get your floor back and probably less dust in the unit too. Plus it's not there to burn you.

 

[Cheese]

If you relocated the thermostat down to where you are, problem solved, you get your floor back and probably less dust in the unit too. Plus it's not there to burn you.

Well kind of yes & no.  [smile]  Another issue you have in a garage without a ceiling is that the temperature setting on the remote thermostat may never get satisfied so that the Reznor never shuts off. Somehow you want all that hot air at the top of the gabled roof back down closer to the floor level.

In Minnesota, over the years we've usually relied on a small gas furnace set on the floor in a corner or a Reznor up in the air but both are ducted to deliver the hot air close to floor level. That also warms up the slab and the heating process is more uniform. The temp level on the thermostat is eventually satisfied so that the furnace/Reznor cycle on & off in a normal manner.

In the last 10 years or so, more people are installing radiant in-floor heating which is relatively economical to operate because of the thermal mass of the garage floor. However, heat recovery is slow so it's usually supplanted with a very small Reznor or electric radiant heater to quickly resupply hot air once the garage door has been opened. The electric radiant heater seems to be the most popular because it's the simplest/cheapest to install.

 

[Packard]

In my niece’s first home, the great room had a two story tall vaulted ceiling.

The heating/AC contractor installed ducting that ran from the peak of the vault to the floor on both ends of the room. 

There was a low power fan in each that could be reversed.  In the winter, they drew the warm air that rose to the ceiling down to the floor.  They could reverse the fan in the summer, but that was really not helpful.

More conventionally, people install ceiling fans.  In the summer, they have it blow down on high speed to help cool the room. 

In the winter, they reverse the fan so that it blows upward, forcing the air towards the ceiling and then down the walls.  This is usually done at a low speed.  Just enough to push the air down the walls, but not so much as to create a prevailing breeze, which would make the room feel cooler than it is.

 

[rvieceli]

I have a small 240 electric heater hanging from the ceiling in the shop (20x20 garage with a 16 foot door) I keep it turned on at about as low as it will go. It keeps the shop above 40 on even the coldest days and usually above 50 in reasonable cold weather. I then don't have to worry about the glue freezing.

To bring it up to a more comfortable working temp, I have a single head "sunflower" style heater hooked to a 20 pound propane tank. It usually doesn't take too long to get up to 60.

The walls are about R15 or so but I put about R60 in the ceiling. Helps a bunch.

Ron

 

[ChuckM]

snip.The electric radiant heater seems to be the most popular because it's the simplest/cheapest to install.

I have two of this kind of heater in my shop for a decade:https://www.leevalley.com/en-ca/sho...MIga-D_Nvt_AIVhxatBh3FrQw7EAQYASABEgL19vD_BwE

According to the specs, it costs me $0.10 Cdn (10 cents) per hour (on the high setting). It's so cheap that I leave it on for 6 - 8 hours after a glue-up or finishing session (turned off before hitting the sack for safety reasons).