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Mac Attack
10-13-2003, 10:21 AM
Hey gang,

My new home's utility room is set up for an electric dryer. We have a gas dryer. I have already ran a gas line for the dryer into the room. The washer receptacle already in place is a 20 amp single outlet. My question is if i replace the single with a 20 amp duplex outlet, will i be ok with the washer and the gas dryer running at the same time on the 20 amp circuit. I know that the gas dryer motor draws 6 amps. I am at work writing this and do not recall how many amps the electric dryer draws. Anyone know right off?

Many thanks in advance.

"There's no way anything can go wrong now."

Wood_Tamer
10-13-2003, 11:17 AM
It will be close, Most washing machines draw somewhere around 12-15 amps, for the newer ones that is. Older machines use a little more.

Depending on the wire in the house.....If it is 12 AWG (12/2 NMB W/Ground) you can put a 30 Receptical in, and up the breaker to 30 amps. This may be your saving grace.

deathwish2
10-13-2003, 01:07 PM
I'm not so sure that 30A on 12-2 is up to code . . . someone will know for sure, but I thought you needed 10-2 or better for a 30A circuit.

As to the original question . . . check the plates (or stickers) on the backs of the appliances or the specs page in the manuals. Take both amp ratings and add them, if it's much over 15A you should not run them both continuously on a 20A breaker. If it's at or under 15A, feel free to shut off the breaker and swap the single for a 20A duplex, and plug them both in safely. If it's much over 15 . . . a second 20A circuit is probably a better idea.

Mac Attack
10-13-2003, 03:01 PM
>As to the original question . . . check the plates (or
>stickers) on the backs of the appliances or the specs page
>in the manuals. Take both amp ratings and add them, if it's
>much over 15A you should not run them both continuously on a
>20A breaker. If it's at or under 15A, feel free to shut off
>the breaker and swap the single for a 20A duplex, and plug
>them both in safely. If it's much over 15 . . . a second 20A
>circuit is probably a better idea.

I'll check the rating on the washer tonight when i get home and go from there.

Thanks!!!!!

"There's no way anything can go wrong now."

SuperDad
10-13-2003, 04:37 PM
If it's already set up for an electric dryer, it should be cheap and easy to change the plug for the electric dryer into a 120V circut. New faceplate, and prying off the little bridge that holds the circut breakers together.

If you really want, I bet you could even make a cord to do it, without even touching the circut breaker panel. You already have two hots, a neutral, and a ground in the dryer plug. Each leg alone should be able to trip both breakers if it exceeds the rating.

michael perata
10-13-2003, 05:04 PM
STOP

12 AWG copper wire is not rated for 30Amps; in residential applications, the max breaker size is 20Amp with 12 AWG wire..

That appliance circuit is designed to carry one load, the washing machine. If you feel comfortable risking your family's safety, then a duplex receptacle will fit in the j-box and at worst (hopefully) the double load will simply pop the breaker, and often enough so that you don't try to run two major appliances off a circuit designed for one.

SuperDad
10-13-2003, 05:51 PM
I'll second that about the 30 amps on #12. It shouldn't ever be done.

According to my "Pocket Ref", 20amps is the max, and even that is limited to 36 feet.

If you want to convert the dryer plug into a 120V circut, you should make sure you have no more than a 20Amp circut breaker on each leg. The cord for the dryer would likely be a weak link if the circut is actually 2 30Amp legs, and if there were a minor fault in the washer, it may start a fire or somesuch.

Wood_Tamer
10-13-2003, 06:17 PM
Well guys, I am not going to dispute you, because I also know exactly where you are looking to get the amp ratings of # 12. I couldn't beleive that what I am saying is right either, however my grandfather who is a master electrician, says that if you install a 30 amp rated receptical, the ones with the sideways "T" slot on the hot wire, that the circuit can now be rated @ 30 amps, I work around electricians in my line of work a lot, and I can tell you I have seen this done in comercial buildings as well, I don't know where the exception is in the code, but it must be in there somewhere, or that many different inspectors are wrong.

Maybe it is just a residential restriction, I don't know, maybe I am wrong.

Just posting my experience.

It is always better to be safe than sorry, so use the #12 and a 20 amp, and run another circuit.

By the way prying off that breaker bridge is a no no also, becasue the breakers are rivited together under the panel cover. Just pulling the bridge off is not truely seperating the breakers, and if someone ever put the 220 VAC back, and didn't replace the breaker, look out.

deathwish2
10-13-2003, 06:48 PM
>By the way prying off that breaker bridge is a no no also,
>becasue the breakers are rivited together under the panel
>cover. Just pulling the bridge off is not truely seperating
>the breakers, and if someone ever put the 220 VAC back, and
>didn't replace the breaker, look out.

I think SD may have been refering to the tab on the side of the receptacle . . . not the common trip bar on the breaker. Popping that off will allow you to have a seperate circuit on each half of the receptacle. That of course requires a second hot to the box. I've got several done this way on my 220v 20A circuit for my shop tools.

michael perata
10-13-2003, 08:29 PM
Here is a reference to the NEMA plugs available for typical usage. http://www.napanet.net/~swdsales/29.pdf

If I intepret what your grandfather told you, the plug in question is a NEMA L5-20(PR). It is rated for 20 not 30 amps. I use one for the AC/Heat Pump in my shop. I use it as a 220v plug by splitting the load so neither side of the plug has more than 10Amps.

It still gets down to wire size, not plug or breaker size.

SuperDad
10-13-2003, 09:58 PM
I was indeed referring to the bridge across the handles of the circut breakers on a 220V circut. Some may be connected under the covers, but I've never seen one.

My current home actually has two independent 120V circut breakers, without the bridge across the handles, for my stove/oven. I've been considering changing that, but never got around to it.

No new circut should be necessary in any case. You already have the wires for the second circut to the destination, and a simple plug change should be enough.

I wouldn't break the tab on the side of the outlets in most cases, although in a few spots in my house one half is switched and the other isn't. It would seem to me to be rather dangerous to run totally independent circuts to the same outlet, for the next guy to touch it.

deathwish2
10-13-2003, 10:58 PM
>My current home actually has two independent 120V circut
>breakers, without the bridge across the handles, for my
>stove/oven. I've been considering changing that, but never
>got around to it.
>
>I wouldn't break the tab on the side of the outlets in most
>cases, although in a few spots in my house one half is
>switched and the other isn't. It would seem to me to be
>rather dangerous to run totally independent circuts to the
>same outlet, for the next guy to touch it.

I've got the same setup with a pair of 110v breakers (20A each) feeding the 220v required by a couple stationary tools. However, I added a bridge, it was a simple metal clip that went across the two levers, they were in a blister pack at Lowes. I'm sure you can find them . . . it could damage your stove if you blew half the circuit feeding it . . . if not just confuse you (i.e. clock works, indicators come on, burners don't heat).

As to breaking the bridge on a receptacle, the circuit I mentioned above is wired 12-3 and has a couple duplex outlets with 'split' power for the stationary tools not yet converted to (or capable of) 220 . . . it is on that same 'Double 20A' breaker, and should never confuse anybody since the source (breaker) is common, and the feed (wire) is in one jacket.

What is scary is two seperate hots from different sources in one box, I found that in my ceiling behind a light fixture, one hot for the light, and another trio of wires coming in . . . a feed and two outgoing lines that dropped into the wall outlets . . . glad I had my 'wiggy' ;)

Mac Attack
10-14-2003, 09:10 AM
Ok, let me see if i got this straight.
My options are:

1. Replace current single 20amp plug with 20 amp duplex plug and run washer and gas dryer on same circuit as long as both machines do not draw over 15 amps together on the circuit.

2. Convert current 220 / 30 amp plug wired for an electric dryer to a 110 / 20 amp plug for the gas dryer.

3. Replace 30 amp plug with a 110 / 20 amp plug and 20 amp breaker in the panel box.

That sound about right??

"There's no way anything can go wrong now."

deathwish2
10-14-2003, 10:06 AM
. . . . it sounds like you've got your options figured out as far as I see them from here. Though options 2 and three sound the same to me . . .

If you convert a dryer plug, you'll need some big wire nuts and short lengths of 12 ga wire to add pigtails, the wire you'll find in there will not fit under the screws of a 20A duplex, it'll be too thick, and possibly be 'stranded' wire as well.

SuperDad
10-14-2003, 06:16 PM
>Ok, let me see if i got this straight.
>My options are:
>
>1. Replace current single 20amp plug with 20 amp duplex
>plug and run washer and gas dryer on same circuit as long as
>both machines do not draw over 15 amps together on the
>circuit.

If you currently have 12gauge going to the outlet, you should be able to up the circut breaker to 20amps. As an experiment, you should be able to find a triple-tap extension cord or adapter(I have a couple 1 foot cords like this). See if it blows the 15 amp breaker, and if not, either live with the triple-tap, or replace the outlet with a duplex.


>
>2. Convert current 220 / 30 amp plug wired for an electric
>dryer to a 110 / 20 amp plug for the gas dryer.

Yes, that would work. I assume you mean to take a 30 amp pigtail and fasten a 110v outlet on the end of it. This might work, but is dangerous due to the 30 amp breaker. Maybe someone makes such an adapter, but I haven't seen it.

>
>3. Replace 30 amp plug with a 110 / 20 amp plug and 20 amp
>breaker in the panel box.

This is probably the best solution, but I bet solution 1 will work just fine without even upping the breaker.

>
>That sound about right??
>
>"There's no way anything can go wrong now."

Mac Attack
10-15-2003, 09:53 AM
I ended up installing a 20 amp duplex receptacle and made sure the breaker matched (it did). All is well.

Thanks for all the input.

"There's no way anything can go wrong now."

SuperDad
10-15-2003, 05:53 PM
I assume you checked if the wire was 12 gauge as well? If not, you should invest in a fire extinguisher, and keep it handy when you are washing and drying clothes at the same time!

Mac Attack
10-16-2003, 10:30 AM
>I assume you checked if the wire was 12 gauge as well? If
>not, you should invest in a fire extinguisher, and keep it
>handy when you are washing and drying clothes at the same
>time!

Yeah I checked, it's 12 ga. I never really checked to see what the old house's receptacle was in the laundry room was until i bought the new house. It was a duplex 20amp as well on a 20 amp circuit. I ran both machines on that for 10 years.

"There's no way anything can go wrong now."