I have calcuated the watts needed for a room to be 2000 watts to heat an addition. I have 240 volt base board heaters. I have double pole thermostats. I am using 12/2 wire. Now my question is... the wiring in the heaters are red/black on the right side and black/black/red on the left side.

Could someone tell me how to properly wire this in layman's terms.. I know it is difficult to explain, but the directions are borderline worthless.

I am using a double pole 20 amp breaker... right?

When I get to the last heater, I don't need to do anything do I? Like run a circuit or anything like that?

You are working backwards. Check the metal label on the baseboard heaters to get the correct voltage (240 does sound correct). More importantly, you need to get the amperage rating for the heaters.

Once you know that, then you can size the wire. 12/3 supports up to 20 amps. If your heater requires more than 20 amps then you need change both the breaker (20 amp) and the wire (12/3 also 20 amp)

OK... I need to get 12/3 wire... it is 240 volt. I have read that you can have up to 4000 watts or 16 feet of heater hooked up to one breaker. Could you walk me through the process of hooking it up though.. from the breaker to the thermostat to the heater.. the wiring inside the heater is different than what I am used to.

I'm confused too with this statement

Quote:

---

Originally Posted by OP

the wiring in the heaters are red/black on the right side and black/black/red on the left side.

---

So, your going to have to help out here.

OK, the rest says
Take the total wattage of the heaters: I = 2000/240
Multiply I by 1.25 = I = 1 * 1.25

Move the size to next higher available breaker size: 15 or 20 A; Use that breaker size

If it's 15 A; 14 or 12 AWG is permissible
If it 20 A; you must use 12 AWG

I'll let you do the math

In general in wiring the wire goes from the breaker to the first heater, to the thermostat and then to heater #1 and then to heater #2 and then to heater #n.

The thermostat must be able to handle the first I: 2000/240

OK... there are places for wiring on either side of the heater. One side has 2 black wires wirenutted together. One of the blacks goes directly into the heater. The other goes into a black cylinder that also has a red wire attatched to it which then goes into the heating element. The other side has a red and a black wire wire nutted together, the red gos into the black cylinder that leads into the element and the black goes into the heater.

Why do manufacturers waste paper and ink on directions.. just a simple how to wire would be great... instead, they clutter the directions and make them too vague.

I know it is a pain, but I need laymans directions to installing. Start from the double pole 20 amp breaker. I have already figured out the amperage and the load is perfect for the 20 amp breaker... so I have 3 base board heaters-1 thermostat-12/3 wiring... then I...

If you are using a straight 240 VAC connection and the amperage is less than 20 amps, then you really only need 12/2. You use 12/3 if you you were going to need 120/240 VAC.

OK, lets assume that the black cylinder is an temperature safety. This is in series with the heating eement. Thus I'm guessing you have a free red and black wire. There should also be a way to attach to ground.

Lets use 3 conductor wire with ground to make things easier to understand. We can change to to conductor later.

At the panel red and black attach to the two pole breaker, ground(bare) is connected to the ground bar, white is capped off.

IF USING 2 CONDUCTOR WIRE, (BLACK/WHITE), YOU TAKE SOME RED ELECTRICAL TAPE AND TAPE THE END OF THE WHITE WIRE RED)

Back to having a red/black/ground

The thermostat should have two wires labeled LINE and LOAD. LINE comes from the breaker box and LOAD heads to the heater. Lets assume 2 red and 2 black wires.

The RED LINE terminal goes to the breaker. The BLACK LINE termonal goes to the breaker. The RED LOAD termonal goes to the RED termonal of the 1st heater. The BLACK LOAD terminal goes to the BLACK terminal of heater #1

Now take the Blacks from the heater #1 and connect to the wire heading to heater #2. Do the same for the whites.

IF there is a heater #2, connect from heater #1 as above.

So when you look at the imaginary picture, there 4 wirenuts with two wirenuts on them at the stat.

Three black wires wirenutted together at the 1st heater and three reds wirenutted at the 1st heater.

The last heater has two reds and two blacks respectively, wired together at the last heater.

If you had three heaters, yes it's possible to branch to either side from the middle heater. That just means more wires together at the middle heater which can potentially be harder to deal with.

Grounds should ALWAYS go to the device first if there is a terminal and your using a metal box.

If the tstat is in plastic box, then just put the grounds together.

The heater probably has a small green pigtail, so all the bares get connected there.

-----

Aside:

Assume you were wiring a duplex outlet in a metal box. You'd connect the white, black and bare directly to the outlet.

With a purchased green pigtail with a screw and an fork terminal, you'd connect the fork to the duplex outlet and the other end with a scre to the grounding screw in the bottom of the box.

Re-labeling:

If it wasn't clear, it always makes sense to re-lable or recode wires used for different purposes. Green isn't allowed to be re-coded.

One use where this should happen is when wiring a 120 V switch where a 2 conductor wire (black/white) is run from the ceiling to the switch. Since it switches the black wire, the white is re-coded at both ends with a bit of black electrical tape to be a black wire.

Similarly, if white is a hot wire on a 240 circuit, it should be re-coded with red tape.

Now you know what all those pretty colors are for:D

Great... thanks..

The thermostat says that the black is the load and the line is the red. The diagram also indicates that the 2 blacks go to the heater and the 2 reds go to the panel. So just to clarify. I am wiring the 2 reds to the panel, then I am wiring the 2 blacks to the first heater. I am running a 2nd line from the first heater to the second heater and then again from the second heater to the third. The third heater is the last heater. Now there is no more wiring after the third heater... right..

Sounds good!

Why are there three wires coming out of a baseboard heater wall thermostat 220v

Quote:

---

Originally Posted by redmeadows

why are there three wires coming out of a baseboard heater wall thermostat 220v

---

Are you asking the original poster? I think this is long done after over a year.

Multiple Baseboard heaters must be connected in parallel in order to work properly!