Hello;
I need a lot of electrical help/advice. I am trying to install an electrical baseboard heater in a basement room (15'X10'). My friend helped me already do the following:
Run the conduit and electrical box for thermostat
Pull all the wires
Mounted the baseboard heater to the wall

We used 12gauge wiring, and G6 Red Wire nuts, and electrical taped all connections. Here is what I bought at Lowe's:

Marley C2500 series Electrical Baseboard heater
specs: 1500W 240V 6.25A

Marley ms26 Line Voltage Thermostat (bi-metal thermostat)
22amp 120/240v single line break

Since neither my friend nor myself have ever messed with baseboard heaters and 240v electrical connections, we asked the person in the electrical department on how to connect these, and he drew out how we should make all the connections, but we ran into some problems. Here is he told us to do:

1) Install a 2pole 15 Amp circuit breaker that matched the maker of my fuse panel (GE). It basically looks like 2 15amp breakers joined as one with their switches connected together.

2) Connect a black 12Gauge wire to each pole of the breaker and run the 2 wires to the electrical box where I planned on installing the thermostat.
3) Run one white 12gauge wire for Neutral (connected to the neutral bar in the fuse panel) down to the heater
4) Run one green 12gauge wire for ground (also connected to the neutral bar in the fuse panel) to the baseboard heater.
5) Connect the 2 black wires from the breaker to the red wire on the thermostat (marked-Line) with a wire nut.
6) From the thermostat-connect the black wire (marked-load) to another black 12 gauge wire with a wire nut and run that down to the baseboard heater.

He then told us for the heater connections to just follow the instructions in the box. We found them to be confusing, so we turned to the internet where I found the following instructions on how to make the connections at the heater. They were as follows:

At the heater
1) Connect the green (ground) wire to the bare wire in the heater with a wire nut.
2) In the heater was a red and black wire twisted together with an orange wire nut. I untwisted them, connected the black wire to the white 12gauge neutral from the fuse panel with a wire nut and the red wire to the black 12gauge wire coming from the thermostat with a wire nut.

Now here is what happened.
When I was finished making the last connection I told my friend in the other room to flip on the breaker for me and I stayed in the room with the heater. When he did he said there was a loud thud and a flash. I went over to him and saw that the breaker looked like it was still in the on position so I fipped it to the off position . I then flipped it back on. There was a loud clang and I too saw an electrical flash. I immediately flipped it off again. There was also a electrical burning smell close to where the breaker was located, but I didn't see any smoke. I stopped at this point because something is obviously wrong. We did exactly what the lowe's person told us, but I don't think he knew what he was talking about. I have yet to remove the fuse panel cover to look at the breaker to see if it is damaged or anything, but I was wondering if someone who knows what they are doing can help me figure this out. In the meantime I left the breaker off and disconnected all the wires. I am also a little freaked out that I may have damaged something (maybe the breaker, thermostat or heater). I hope not. Anyway, thanks in advance for your help..
Eric

What I like about Lowe's is that nobody bothers me while I am looking around, or at the most, they ask me about my dog.

Your heater has a loop in it. What you want is for power to flow from one pole of the box to the thermostat, and then to one terminal of the heater. Power then flows through the loop the heating element makes, and then back the other wire to the other screw in the other pole of the breaker. You also want the ground wires connected to each other and to the metal housing of the heater. Usually there is a green screw for then. Most, maybe all, 240V heaters don't use a neutral.
You can run regular 12-2 with ground. Connect the white to one pole of the breaker, and the other end to one terminal of the heater. Mark both ends with black tape or paint.

I find it more likely to have people ask me what I am looking for at Home Depot. I don't think I have ever asked them any questions, so I have no idea how good their answers.

Oh, by the way, if you connect both hot wires to the thermostat like the Lowe's guy said, when it is closed, you will have a dead short.

Both Lowe's and Home Depot are HORRIBLE for customer service. Home Depot is worse. Menards is the best, and they have the best prices, but I STILL wouldn't trust the instructions from anyone working there. This is what small local hardware stores are for.

Yes, the contacts inside of the new 2 pole 15 amp circuit breaker are now damaged from the dead short, and will problably continue to work for a period, but will fail in the future.

You were entirely mislead and received poor, inaccurate, and dangerous advice from the clerk at the store.

Remove the new breaker and return it to the store for replacement, and be sure to speak with the Head manager of the store to explain that his employee is offering advice about a regulated profession that will someday cause a fire, injury, or fatality, and that in most states only licensed tradesmen are allowed to work on or offer advice.

Does anyone ask the kid stocking the shelves in a drug store about medical advice?

The advice on how to properly connect the circuit you have already received from the previous answers is correct.

Ah, Lowe's. My daughter worked in their lawn and garden area the summer after she finished high school. She was actually very knowledgeable in some areas having been active in what is called Envirothon, her team winning the state championship 2 of her 4 years and going on to nationals. The one customer was upset when she tried to fob yews off on him when he asked fro Taxus.

The plumbing department was between L&G and the break room. She always went around it because there were always customers that looking for somebody to ask questions.

First off I would like to say thanks to all of you for your quick responses. :) I wish I really would have gotten professional advice before I did what the lowe's person told me. Oh well. Anyway, I forgot to also state in my original post that the instructions with the thermostat use L1 and L2 and I am not sure what those mean (I am use to wiring instructions saying "hot", "neutral" and "Ground"). I also do not know what you mean when you say "run regular 12-2 with ground", so I wanted to confirm what I need to do before I do it. So with that in mind, according to Labman, I need to do the following:

1) Connect one of the black wires from the 2 pole breaker to the red wire on the thermostat that is marked "Line".

2) From the Thermostat, connect the other black wire marked "load" to one of those twisted wires of the baseboard heater.

3) Connect the second black wire from the 2 pole breaker directly to the other remaining wire on the baseboard heater (completely bypassing the thermostat).

4) Leave the green ground wire from the fuse panel connected to the bare ground wire of the heater. Also tie in a third ground wire from these to the green ground screw on the thermostat so it is grounded as well.

5) Disconnect and remove all the white neutral wires because a neutral wire is not needed.

Some questions I have from the above steps are:
Why is the neutral wire not needed?
According to the heater wiring instructions, it doesn't matter which of the 2 twisted wires I connect first. Is that correct?

About the breaker. So it is definitely damaged and I shouldn't use it anymore? If that is the case, then I will replace it, but the problem was I had to special order it from a GE parts distributor. For some reason none of the local home improvement stores seems to carry GE 2 pole 15amp breakers (Part number THQL2115 2p15a 120/240). I looked at Lowe's, Home Depot, Menard's, and the local Ace and True Value stores. No one carried them. They weren't that expensive, but it took a couple of weeks for it to come in. I do have another one I can use that was actually going to be for the 2 additional heaters I have yet to install. Do I need to worry that I may have damaged anything else (fuse panel, the thermostat, or heater)? Sorry about all the questions that I have. Thanks again for your help.

Yes the breaker is damaged. Don't worry about ordering a 2P15 amp breaker, trade it in for a two pole 20 amp breaker, which should be in stock, and cost the same.

Now follow me I will go through the entire circuit from beginning to end, using the 2 wires already installed.

At the breaker, connect the two wires to the two terminals on the 2 P CB, one wire each for each terminal.

At the stat, connect the two wires FROM the breaker to the two wires labeled L1 & L2 on the stat, one each to one each, does not matter which to which.

NEVER bypass a two pole 240 volt thermostat as you proposed.

Connect the two wires FROM the stat labeled LOAD to the two wires going to the heater, one each, does not matter which one to which.

At the heater connect the two wires from the stat LOAD wires to the two wires at the heater.

Leave the green wires at each location as is.

I notice you use conduit and pulled wires, I get that you pulled a black, white and green.

You can use the white as a hot connected to the breaker, and color the white wire with black tape at the breaker, stat and heater. Or if you removed, or added another black wire, then this is fine also.

The 2 pole breaker connects to both hot legs in the panel, which is 240 volts. A neutral is only used for 120 volts, each jot leg to neutral will measure 120 volts. The neutral is not needed for a standard 240 volt circuit.

I added a simple wiring diagram to help.

The part number for a 2 pole 20 amp CB will be GE # THQL2120

Do not let my advice confuse you. Some thermostats just switch one pole. Tkrussel's diagram is exactly right for the proper 2 pole 240 volt thermostat.

Oh, Kevin, be sure and look at https://www.askmehelpdesk.com/heatin...ems-50240.html I guess as a dumb DIY, I shouldn't disagree with a professional.

I threw out the damaged one, and installed the spare 2pole 15Amp breaker I had. Your explanation and diagram really helped me understand how the circuit worked. Since the 1 pole thermostat confused me, I returned it for a 2 pole 240V 22Amp honeywell thermostat that has the 2 red (line) wires and 2 black (load) wires. I then re-did all the wiring as follows:

1) I removed all the white neutral wires that I pulled.
2) From the newly installed breaker I connected the two 12AWG black wires and at the other end I connected them to the 2 red (line) wires on the new thermostat.
3) The 12AWG green wire ran from the ground bar in the fuse panel is ran to the thermostat. I then connected a ground wire from the thermostat to it and to the ground wire on the heater. Now the thermostat and heater ground wires are all connected to the ground wire ran to the fuse box.
4) I then pulled a new 12AWG black wire from the thermostat wall box threw the conduit to the heater.
5) So not from the wall box of the thermostat I have 2 12AWG black wires running to the heater. I connected one end of these 2 wires to the black (load wires) on the thermostat and then the other end of the wires are connected to the 2 black wires of the heater.
6) I double checked all my connections to make sure that all wires were connected like the diagram and that they were securely connected with wire nuts and taped up with black electrical tape.

I then flipped on the new breaker and the heater is now working! Thanks again for everyone's help. :)

Now I still have two more of the same heaters I want to install in a different room on a new circuit. I have looked over the instructions of the manual for the heaters, but I want to be sure that I am correct before proceeding. Since I am going with two of these 1500watt heaters, I thought it would be best to go with a 2pole 20amp breaker (that one tkrussell suggested). Now the heater doesn't explain how to hook up two heaters to a single thermostat, so I just looked at how I did the one, and then added a second one onto it. Here is my thinking:
1) I would wire the breaker to the thermostat like before (two black wires from it to the two red-Line wires on the thermostat).
2) Then from there it is different. I would wire one of the black-load wires of the thermostat to the first black wire on heater one.
3) Then the other black wire from heater one I would wire to the first black wire on heater two.
4) Then the second black wire on heater two I would wire back to the last remaining black wire on the thermostat thus completing the circuit.
5) Lastly I would tie in all the grounds of the heaters and the thermostat to another main green ground wire that runs back to the fuse panel. I have made a picture of my connections shown below. The blue wire represents the wire going from heater one to heater two. If you could take a look at my drawing and my explanation and let me know if this is correct. If not, could you please let me know what I am doing wrong or need to change. Thanks again. :)

Attached Images

 

I modified your sketch, and changed your explanation to reflect the changes:

2) Then from there it is different. I would wire one of the black-load wires of the thermostat to the first black wire on heater one, AND #2
3) Then the other black wire from heater one I would wire to the SECOND black wire on heater #! AND two.

See if it makes sense.

Why are you just going to "discard" the damaged breaker, when it's failure was caused by the imcorrect advice by the store clerk? Someone needs to let these stores know that their employees giving bad advice is going to cause someone serious problems, and a lot more than just a damaged circuit breaker.

Thank you for checking this for me. After looking at this, I see where my mistakes were with my diagram. I have hooked it up now using your changes and it is working great!

I agree with you 100% and normally I would have, but I was a little time constrained at the time. I will try to get back to that store and talk to the electrical Department manager so maybe some change could happen in the future and a situation like I got into can be avoided by some other poor customer.

Thanks again for all of your help and instructions you gave me. I couldn't have done it without you and I really appreciate it. :)
Take care,
EricC

I have the same scenario as the user below... however I'm linking in four heaters total (or hope to). I'm using the same honeywell 22A double-pole thermostat... and four different baseboard electric heaters (2x6.25Amp, 1x5.2Amp,1x3.13Amp). My question is, as long as this adds up to less than the 22A threshold for the thermostat is that code? Also, is a 20amp double-pole breaker sufficient for that set-up? Not sure if I have to take watts into consideration, but the total Watts add-up for the four heaters total 5,000 watts. Any help would be appreciated.

No, this circuit will need to be a 30 amp circuit with all #10-2 wire with ground cable. Your better off using two 20 amp circuits, then you can use all #12 wire.

I like the 2x20amp and using #12 wire idea. When you say that do you mean two completely separate circuits? As in I'd need two thermostats instead of one?

If I installed a smaller fourth electric heater to keep the total of the AMPS below 20--would I then be OK to use only one double-pole 20 amp breaker?

One other possibly code related question. And I'm sure this one varies by region... I'm using 2x2 framing (this is a basement application). Normally does that dictate the use of conduit? Or is using NM still OK as long as I use metal plates on the studs to protect the drill-through holes?

Thanks for your help!

The total amps of a 20 amp heating circuit needs to be 16 amps or less.

As long as protective plates are used as you mention , then NM is fine. We usually run up over and down to eliminate all the drilling and plates. With the cost of copper so high, running horizontally is probably more cost effective.

Thanks. OK, one more question then (I'm sure you get that a lot): when you said: "No, this circuit will need to be a 30 amp circuit with all #10-2 wire with ground cable." The thermostat is rated to 22amps... would a 30AMP circuit with #10-2 wire be safe in combination with this 22amp thermostat?

If it were you---would you go:
Option A: 30 amp circuit, #10-2 wire and 22amp thermostat with 21amps of total heating
or
Option B: 2x20 amp circuits, #12-2 wiring and a 22 amp thermostat for each circuit, and the 21amps of total heating divided up roughly evenly between the two.

My vote is for #2. If there is a problem with one, the other will continue to serve heat.

#10 is more costly, and difficult to work with.

The previous wiring diagram in this post describes a double-pole setup for two heaters. The instructions for my two heaters are indicated the below---is this also acceptable? Is it the same method, just a slightly different approach? My diagram assumes the ground stays the same and orange and red indicate my new approaches to blue and black.

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No, need two entire circuits, so add a breaker and another stat, and feed the purple orange wires with this circuit. Be sure to disconnect these from the other circuit at the stat.