garage heaters

[clark....]

Merry Christmas, everyone! I'm looking to put a ceiling mounted heater in my garage workshop. I'm looking at models that are 5000w and 240v. Rather than hard-wiring the unit I'd like to have it corded and use the existing 240 plug I use for my table saw. Since the table saw isn't used constantly I figure I could just have the heater plugged in and swap for the table saw as needed. Is there any other concerns with swapping devices plugged in to a 240 outlet? Most heaters that are 5000w or higher say they require being hardwired. However, there is a Dr. Infrared Heater DR-988 Garage Shop 208/240V, 4800/5600W heater that comes with a 6-30R plug factory attached. If this one comes with a factory plug attached, why can't I buy any other "hard wired" unit and put a 240v plug on it?

[krw]

I don't see a problem with this as long as the current circuit is 10Ga wiring with a 30A breaker. Note that the 6-30R is a 30A plug. This is sort of circuit is a little unusual for a table saw, which are usually connects to a 20A branch. I have several power tools (table saw, bandsaw, and lathe) plugged into the same 240V circuit, with the assumption that I can only use one at a time. My dust collector is on a separate circuit of its own because it will be used together with these tools.

The units intended to be hard wired may only have UL certification for this use. Using them with a plug may technically be a violation of the code. There is nothing to say that it won't work but it's not the intended use, as long as the power doesn't exceed the capability of the circuit.

[dpb]

You can do whatever you like; as another said it will violate the UL listing for the other unit, but as long as the circuit is of sufficient ampacity for the unit, it'll not be a safety hazard.

But, if it's in the garage and ceiling mounted, why wouldn't you just go ahead and hard-wire it? If the plug is somewhere convenient that you can swap it easily, it's going to be a fair run and leave a long cord just hanging.

I'd suggest to "bite the bullet" and do it right.

[Just Wondering]

Have you considered a heat pump? They're cheaper to run that those heaters, and give you cooling in the summer. Something like this:

[J. Clarke]

And if there's a spare circuit in the panel it can even run independently of the dryer.

Of course I shouldn't talk--I have 80 feet of 10 gage stranded wire running from an outlet to where I charge my car.

[clark....]

On Saturday, December 26, 2020 at 11:54:02 AM UTC-8, [e-mail] wrote

It is a 20A branch so I assume 12 gauge wire.

The 240 outlet happens to be right below the perfect spot to hang a heater. The heater cord would only have to be 7 feet at the most. I'm hoping to save a few bucks by not installing a new breaker, wire, and outlet.

[krw]

Not enough power. 5000W/240V = 21A You need a 30A circuit. Your plug is rated for 30A. No way around this one.

I doesn't matter. You don't have enough power for it.

[clark....]

Perfect! Thanks for clarifying. Budget calls for a cheap solution, so I need to find something that is no more than 4800W. Someday I'll go big. For now I just need something that can take the chill off better than an office space heater.

[Clare Snyder]

I use a 4000 watt construction heater - the orange cube. It shares an outlet with my compressor and my arc welder. It is a fan forced unit about 14? inches square. About 13.5 BTU output.

[DerbyDad03]

This may be too small of a solution, but I'm a big fan of the oil filled heaters. I run mine on low 24 x 7 in my basement shop. 3 exposed concrete block walls.

Perhaps 2 or 3 of the biggest of these in various locations would be enough to take the chill off in your garage:

Perhaps keep it on low all the time and just crank it up as needed.

[krw]

No, you need to target less than 4000W (3600W?). At 4800W, you're too close to the edge. At the maximum line voltage the heater will draw

21A.

[Scott Lurndal]

IIRC, you can only draw 80% of breaker capacity on a continuous load, call it 3.5kw in round numbers (3.8 max).

[clark....]

Yes, the 4800w's that come corded have a 6-30P plug. Therefore, I'm going with this one - Cadet 4000-Watt Electric Garage Heater. It has a 6-20P plug, so it should work. Currently I'm using a 1500w office space heater and it works ok if a have it right next to me on the bench. I'm hoping at almost 3 times the wattage, this one will suffice. I don't need a sauna. Just warm enough to relax a little.

[knuttle]

and have the glue and paint to dry properly. At least that is the problem I have when it is cold.

[krw]

You could use both. I might use an infrared heater where you tend to work. I'll keep you (well, half of you) warm without sucking up too much power.

I don't use a heater because my (walk out) basement only gets cold for a few weeks out of the year (it's 58F now and may get down to about

50F). Once I get working a sweatshirt is good enough.

[DerbyDad03]

58? Probably won't see that around here for a while.

My daughter asked me to bring one specific tool when we went to visit for Christmas. I brought it, but I made her use it.

[krw]

That works for me. The kid is still in VT. They had 32" a week or so back. You can have that white s***. I'm done with it. The average highs are in the 50s and 60s (lows in the 30s and 40s), November through March, here. Nice weather.

I was referring to the basement temperature. There is insulation between the unheated basement and the first floor but it's not a lot. No point in it.

[Dave Marulli]

Yep...that's the same storm that hit my daughter's area - central NY, 10 miles north of the PA line. Reports say 40", she probably got mid-30". By the time I showed up with the snow blower (4 days later) it had melted down/sunk a bit so it doesn't look like that much, comparatively speaking.

Of course, the day I loaded the snow blower back into the trailer, the plows came by to do their "street widening" runs. Knocked down the 5' piles at the EOD and blocked me in and my daughter out. I had to unload the blower and clear the EOD of the hardpacked, frozen blockage.

Back here at home, it's 27°F outside, 60°F in my basement shop. It'll drop into the low 50's if temps hit the teens. The shop is small enough that a 1500W oil-filled space heater will warm it up nicely. After 30+ years, I've not seen any indication of rust due to the fluctuating temps, so I'm counting my blessings for that.

[krw]

Yeah, I remember all that. I was in the Hudson valley for just short of 20 years and Vermont for 14. There are a lot of reasons I'm no longer in the NE but that's high on the list.

My shop will hit the low 50s, as well, but it's a walk-out so is only about half below ground. The rest is stick built like the main floors. In the summer it'll get into the low 80s without help. I don't heat the space but I do have a small AC (1T, IIRC) and a dehumidifier. I try to keep the humidity down to 50-55%. Electricity is fairly cheap so it's not a big deal to run both at once. I have too much cast iron to risk.