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Convert 30amp/220volt/2 pole to 15 or 20amp/110volt/1 pole

Convert 30amp/220volt/2 pole to 15 or 20amp/110volt/1 pole

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  #1  
Old 07-30-18, 10:38 PM
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Convert 30amp/220volt/2 pole to 15 or 20amp/110volt/1 pole

Hello =)

Basically, I want to pull out my 2 useless floorboard heaters from the upstairs bedrooms which are on a dedicated 30amp/220volt/2 pole circuit and insert/replace with standard 110volt electrical outlets. I want to do this so I can use 2 portable AC units, which are currently overloading the existing circuits when running at the same time. And it is... HOT!!!

Can I leave the wiring alone and change out the breaker in the service panel and add new receptacles in the bedrooms? There are also wall mounted thermostats for each heater. There are 3 sets of wiring coming into the first thermostat box (top left, top right and bottom left). Haven't pulled the second thermostat yet. All wiring is black/white/bare.

Heater circuit breakers are the bottom ones on the left. I have both the upstairs and the downstairs shut off, but I am only interested in modifying the upstairs.
 
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  #2  
Old 07-30-18, 10:42 PM
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Welcome to the forums.

You can convert that 240v 30A line to a 120v 20A line. That's it.
A 120v receptacle can not be connected to a breaker any larger than 20 amps.
Will that be enough for your needs ?
 
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Old 07-30-18, 10:47 PM
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I would think that would be OK. I just want to pull 1 AC off the current 15amp/110volt circuit as 2 are tripping the breaker.

I think I want to hire an electrician as I am not supper confident about how to do all of this work. I'm guessing since all the wiring is OK, it shouldn't take more than about an hour in each of the 2 rooms?
 
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Old 07-30-18, 11:01 PM
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From what you've described...... the wiring is all ok. The wires would be connected together at the thermostat locations so that they just pass thru. A blank plate can be used or the stat put back in as a dummy. The wires would need to be removed from the heaters and installed in electrical boxes for the receptacles. The 2P30A breaker would need to be replaced with a single 20A breaker and a blank. I could see about two hours for the whole job.
 
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Old 07-30-18, 11:06 PM
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Thanks, Pete!!!

Yeah, that's about what I figured. I'm just going to pull the heaters off as they are above the floorboards and just against the wall, so pretty easy. Will put new boxes in for the wires and outlets.

I know just enough to be dangerous, so I think I'll leave it to a professional =)
 
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Old 07-31-18, 01:47 AM
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OK, I think my original specs were a bit off... It is a dual pole breaker, but I believe it is 15amp, not 30... Especially since it's all 14 gauge wiring... I thought since it was 2x15 that would mean 30, but it doesn't, right? 30amp requires 10 gauge wiring?

Still should be able to completed my intended project, I think?
 
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Old 07-31-18, 04:28 AM
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A double pole 15 is still 15 amps.

You will need to see.if the wiring has a neutral before.splitting into two circuits.
 
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Old 07-31-18, 06:56 PM
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Here is a basic wiring diagram. Maybe someone might shed some light on the best way to complete what I'm looking to do (above)... Thermos will need a pass-thru...

http://i64.************/oqln5d.jpg
 
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Old 07-31-18, 06:59 PM
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Man, I cannot figure out how to upload an image anyone can see. Arrrrgggghhh!!!
 
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Old 07-31-18, 07:07 PM
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One more try...blah blah blah
 
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Old 07-31-18, 08:24 PM
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Of you have only.black.and white.on the breaker you will need to move the white to the neutral bus.for.a.120 volt circuit. You will not be able.to.have two circuits.
 

Last edited by pcboss; 08-01-18 at 03:51 AM.
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Old 07-31-18, 09:12 PM
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1 circuit is fine. In fact, I don't even really need to have a live feed at all into the second bedroom. I only need 110v in the master at the wall behind the heater. I guess my confusion is knowing the wiring path and where the three cables go from the master stat...
 
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Old 07-31-18, 09:42 PM
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The two cables on the left are power in and power out.
The cable on the right goes to the master bedroom heater.

You will need to remove the master bedroom stat. Open up all the wiring connections.
Find which cable is the line from the panel using a meter or voltage tester.
This cable is the one you want.

The cable that is dead goes to the other room stat. This line will be capped off.
All grounds remain connected together even on the dead cable.
 
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Old 07-31-18, 11:15 PM
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Thanks for your help!!!!!!!!!!
 
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Old 08-01-18, 04:59 PM
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So, just wanted to make sure about this part as this is where my knowledge is not very good. In the panel, I can simply DE-ENERGIZE the entire panel and move the neutral (white) from the dual pole circuit breaker to the neutral bus and re-energize, thus providing 120 volts on one single 15 amp circuit (even though it is dual pole). Or do I need to buy a new single pole breaker and swap it in the panel?
 
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Old 08-01-18, 05:09 PM
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Yes..... white gets moved to neutral bar.
You should try to find a 15A single breaker but it can remain on that one.
 
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Old 08-02-18, 03:47 AM
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All is working like a charm!! Thanks to all who helped out. Seemed daunting at first, but worked my way through it slowly, carefully and safely (always shut down power first) and saved some dough and completed the project by myself!! Again... Thanks!!!

The only thing I still don't quite get is why keep the ground (bare) wire connected on the dead cable? Just more ground points?

Check out the fit and finish behind the heater via framing hammer by the builders. Ha!!! Sheet-rock repair is my next project!!!
 
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Old 08-02-18, 09:29 AM
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Typical neat installation.

As long as the circuit is intact...... brought into the junction box.... the grounds must remain connected.
If you wanted to cut the cable to the other thermostat..... then the ground would be removed.
 
 

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