wiring garage heaters

[Boones]

Hi I recently purchased two 5000 watt heaters for my garage (Model FUH54). They were from Northern Tool and had good reviews. They are 240v, 30amp. I am getting ready to wire them and have a question. They said to use 10-2 wire but since its a 240v, shouldn't I use 10-3 per today's codes.

Per the instructions it states to use black to terminal L2, White to terminal L1, and Copper ground to ground lug. Can I use 10-3 wire bu using black to L2, Red to L2, white to Ground lug and copper to a screw on the chassis. (and the 4 wires to my fuse panel. Or do I use 10-2 and only use one ground (the black and white to the power on the breaker and copper to the panel grounding terminal block..


Here is a link to the manufactures site and install document
http://www.marleymep.com/en/fahrenheat/products/utility-heaters/huh524.aspx

 

[Stuart in MN]

You only need to use 10-2 with ground. Some devices, like kitchen stoves or clothes dryers, will use 10-3 but that's because they need the neutral wire for 120vac power (for the clock, timer, etc.) Those heaters only need 240vac, therefore no neutral wire.

 

[Boones]

stuart, so I am clear. both the black and the white will go to the 240 30amp breaker and the ground to the ground/ neutral buss bar on the panel..

if this is wrong, how is it wired

 

[sparky0908]

Yep... That's right

 

[Boones]

thanks for the confirmation. I just finished wiring the breaker and hit the switch. they are running and heat is flowing. I had wired it all except that last bit as I thought they should be but wanted to double check before throwing the switch....

 

[Boyd Who]

Let us know how those heaters work out for you. I have a single 4800-watt 240V unit in my 20x22 and it works fantastic! Keeps the shop at a constant 50F even when it's -30 outside, and maybe runs 20 minutes out of every hour.

 

[Toddyus]

I thought I would bring this thread back from the dead, rather than start a new one.

I have a similar (same?) heater and plan to hardwire it to the panel. However, my walls will be drywalled and I can't envision some conduit and or wire just emerging from the wall into the heater. What's standard practice here if you're not going to use a receptacle?

Do people hang a box and connect wire inside the box? Something else?

An electrician is going to install and connect everything to the panel. I just need to figure out how to run the cable...

 

[Falcon67]

I'd encourage you to consider a nice twist lock receptical - I spent $50 on wire and $40 on the socket and plug LOL. It makes it rather easy should the heater need to come down for cleaning or other servicing. Other than that, I think you'd use a 10-2 whip and come out of a 4" box mounted flush with the drywall. You could drill out the cover for the cable termination/clamp if you can't find a cover with the right size hole.

 

[Toddyus]

I'd encourage you to consider a nice twist lock receptical - I spent $50 on wire and $40 on the socket and plug LOL. It makes it rather easy should the heater need to come down for cleaning or other servicing. Other than that, I think you'd use a 10-2 whip and come out of a 4" box mounted flush with the drywall. You could drill out the cover for the cable termination/clamp if you can't find a cover with the right size hole.

I've considered this, but mainly was shying away from it because of the added cost. The heater is a 30 amp, 250V, 2-conductor (with ground). I didn't check an electrical supply house, but the only 10-gauge cord wire I could find at HD was 10/4. I assume they make a 10/2 cord wire?

I do kind of like the idea of adding a flush-mount junction box and attaching some flex conduit to it from the heater.

I presume the reason they specify that the heater be direct-wired is for heat and fire-rating purposes, no? Is it an issue if I either cobble together a cord/receptacle solution or join two wire together with wire nuts in a metal box?

 

[Falcon67]

I used 10-3 w/gnd heavy cord from HD, just didn't use the 3rd wire. It was what they had in stock, good nuff. I would not think there would be much difference in any rating between a good twist lock connection and hard wired. The plug wasn't cheap - and when we moved, I took the heater, plug and wiring with me! Look at whips for either electric stoves or water heaters - if they have any. My 5kW heater pulls 20.5 amps, so I just made sure to use 30A rated pieces.

The socket will be mounted flush in the now shop since there will be sheetrock, but here's how it looked in the old shop:

 

[Toddyus]

I used 10-3 w/gnd heavy cord from HD, just didn't use the 3rd wire. It was what they had in stock, good nuff. I would not think there would be much difference in any rating between a good twist lock connection and hard wired. The plug wasn't cheap - and when we moved, I took the heater, plug and wiring with me! Look at whips for either electric stoves or water heaters - if they have any. My 5kW heater pulls 20.5 amps, so I just made sure to use 30A rated pieces.

The socket will be mounted flush in the now shop since there will be sheetrock, but here's how it looked in the old shop:

All right, I'm inspired. This is essentially the same heater I have. Going to pick up the parts tonight...

 

[Jamech]

Is there any limit on how long the cord on a heater like this can be? I have a 6x16 beam across the center of my garage I would like to attach a heater to but the 30A outlet is near the breaker box at the front of the garage. It looks like about a 20 foot long cord would be needed to reach the outlet.

Jamech

 

[Toddyus]

All right, I'm inspired. This is essentially the same heater I have. Going to pick up the parts tonight...

Ok, so I got a turnlok receptacle and plug and wired it up on both ends with 2-conductor (plus ground) #10 wire. The heater only has mounting points for 1 neutral, one hot and one ground.

I am not making the connection to the panel, but I really don't get how 10-2 wire is going to connect to a 30 amp, 250v circuit. I know very little about 250v wiring, but doesn't it need two hots?

Can anyone shed some light on this for me? Is my setup going to work?

 

[mrbreezeet1]

Yeah, 2 hots and a ground.
Shouldn't be a neutral.
What kind of heater is it?
Same as Falcon's?

 

[Toddyus]

Yeah, 2 hots and a ground.
Shouldn't be a neutral.
What kind of heater is it?
Same as Falcon's?

Branded under a different name, but essentially the same heater as Falcon. Here is a picture of the wiring instructions from the manual. This is all they have and now I see it doesn't say "neutral," it just says "white" wire. Is the white wire in this application supposed to be repurposed as a hot?

 

[mrbreezeet1]

Yeah, They are using the white as a hot.
Usually remarked Black.
See In this one there saying L1 & L2.

 

[Toddyus]

Yeah, They are using the white as a hot.
Usually remarked Black.
See In this one there saying L1 & L2.

L1 & L2 as in "Leg 1" and "Leg 2?"

 

[mrbreezeet1]

L1 & L2 as in "Leg 1" and "Leg 2?"

Yes, Leg 1" and "Leg 2.
It is the 2 hots off your 2 pole breaker.