Are the 4-prong 240v outlets GFI/GFCI?

My friend is moving his washing machine and dryer in to the bathroom (which is adjacent to the existing laundry room) because the floor in the laundry room is unstable and joists need to be replaced (but he can't afford it right now)-- it's also just very inconvenient to get in to it and he wants to make it in to a mud room. He's already moved the washing machine in to the bathroom, but he is worried that the outlet for the dryer will get messed up due to steam from the shower. He currently has the 3-prong and I've read that they can be a shock hazard.
If he gets a 4-prong one, do they come with GFI/GFCI protection? Or would they be safer to use in a damp area?
Another question: Could we use the same wires that are running to the existing 3-prong 240v outlet for the 4-prong outlet and somehow add a ground wire? If so, how would that be done?

zannej said:

My friend is moving his washing machine and dryer in to the bathroom (which is adjacent to the existing laundry room) because the floor in the laundry room is unstable and joists need to be replaced (but he can't afford it right now)-- it's also just very inconvenient to get in to it and he wants to make it in to a mud room. He's already moved the washing machine in to the bathroom, but he is worried that the outlet for the dryer will get messed up due to steam from the shower. He currently has the 3-prong and I've read that they can be a shock hazard.
If he gets a 4-prong one, do they come with GFI/GFCI protection? Or would they be safer to use in a damp area?
Another question: Could we use the same wires that are running to the existing 3-prong 240v outlet for the 4-prong outlet and somehow add a ground wire? If so, how would that be done?

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The easiest way to get gfi protection would probably be a double pole gfi breaker. I am not an electrician, but I have never seen one of those. Perhaps a real sparky will be along soin.

If the existing 240V supply is in metallic flex or EMT, or if it is romex with a ground you simply bond the appliance to either a metal box or the ground conductor.

Here is a link to 240V GFI's, or if you know the brand of the service panel you can search that way;
https://www.shop411.com/shopping?qs...q=240v gfci breaker&dqi=&am=broad&an=google_s

Thanks, Soonyb! I have been reading up a little and saw somewhere that GFI might not be a good idea for a dryer and there aren't any outlets sold with GFI for dryers (something about them tripping a lot?)-- BUT there are circuit breakers that are sold in GFI and would be sufficient. I think the outlet that would be needed, if he went with a 4-prong, would be a 110/250v 30amp outlet. Although, I'm confused with "surface mount" and "flush mount" outlets. Do the surface mount ones mount outside the wall?

I believe there are currently only 3 wires for the outlet, so I'm trying to find out the proper way to add a ground wire. Would it have to run all the way back to the box? or could he run the ground to somewhere under the house after attaching it to a screw in the box?

WAHOO, my 1st notification. Things are looking up.

If they have a propensity to trip, it would be at initial startup.

Do not install a 4 prong recepticle unless you have the require 4 conductors from the service.

Yes, surface mount is a metallic fixture box mounted on the outside surface of the wall and a flush mount resides within the wall cavity with just the face of the recepticle and the trim showing.

If the existing feed is in metallic flex. or EMT you can fairly easily pull and additional ground conductor. If it is romex, and easily accessible, you can replace it with 4 conductor.

Thank you!

I'm not terribly familiar with electrical terms so I'm not sure I understand what you mean by "4 conductors from the service". By service, do you mean from the breaker? I've found 4-prong plugs that can be attached to modern dryers (and mine can use either 3 or 4). I also found a Leviton 4-wire outlet that says it is "self grounding". But I don't know what the wiring requirements are. Would 10AWG with 3 wires work? (neutral and two hot?)

I have no idea what the existing feed is. I don't know what metallic flex or EMT are either.

I'm thinking about this upgrade for my friend's house and for my own. My friend's breaker box is about 60' away from where he would install it and he can't really afford to buy new wire. I'll have to get him to look and identify what his current wiring is. It was a meth house that he's fixing up so it had all sorts of code violations and problems.

In my house, the outlet is just on the other side of the wall from where I want to move it-- I just want to flip it the opposite direction and flush-mount it inside the wall. The breaker box is maybe 10' away.

Another question: If my friend installs a vent fan to get rid of moisture and doesn't touch the dryer outlet much (no unplugging unless it's an emergency or something) is it likely to be ok in a damp area? I'd suggest flipping the breaker to the dryer when people shower, but I don't think his girlfriend would remember.

I really appreciate the responses. I'm hoping to gain a better understanding of wiring. That way I can at least spot when something is wrong if I see things or maybe correct issues with bad wiring in my house (although, I'll defer to experts and make sure it's the right thing before I touch anything electrical).

All the information provided to you so far is accurate and correct.

The outlet (receptacle actually) that you showed the link to is a NEMA 14-30R which is the one needed for a safe hook up of a dryer on a two pole 30amp breaker. You will need 10/3 w ground; this has two hots, one neutral and one ground wire (4 wires total). You would be defeating the purpose of the 4 prong receptacle if only using a 10/2 w/ground (two hots and a neutral-3 wires total). You want that ground wire specifically for protection.

There are 30 amp two pole GFCI breakers but it highly is dependent if they are in fact available only because of the brand and model of the breaker panel that your friend has. Your friend will have to determine the brand and model number of the panel that they have first. Then find out if a GFCI two pole 30 amp breaker is available for that panel. BUT do not use a breaker that is not rated for that panel specifically only because it works or fits into the breaker panel. That is going to be a very big mistake. Many people when searching for a breaker rated for their panel realize that there may not be one available because of the age of the panel or the price of the breaker is very expensive so they end up looking for a breaker of the same amp rating that is less expensive that happens to fit in their panel. This is a very big mistake and can possibly cause personal injury and if the breaker causes any property damage as in the way of malfunctioning and you have to bring in your home owners insurance company for a claim the insurance company will more than likely if not 100% sure will NOT cover the claim because the improper breaker was installed in the panel.

EMT is a conduit used in electrical work. Short story, it is a metal tubing of different sizes where individual conductors are run thru the tubing. Many references to it on Google.

Terminology of wires/conductors opposed to cable/romex.
Wires and conductors are basically the same concept however can be found in many different sizes. Wire or conductor is one wire or conductor. Romex is a trade name used widely in general now for a cable which has multiple wires or conductors within the same enclosed sheathed insulation and each of the wires/conductors have their own insulation protecting them.

What was being said that if conduit or EMT is being used to run the conductors or wires to the dryer receptacle and not romex/cable then the EMT would act as the grounding source.

The receptacle (NEMA 14-30R) where you reference "self-grounding" is not grounding by itself as it still requires a ground from the receptacle back to the panel. Unfortunately some of the specifications are misleading in that respect.

Thanks Afjes.

I'm sure you have seen these products when wandering around home desperado or low-n-brow, here are a couple of links;

https://www.gamut.com/c/electrical/...vD_BwE&gclsrc=aw.ds&q=electrical+metal+tubing

https://www.grainger.com/category/f...nd-carrier-systems/electrical/ecatalog/N-18nq

zannej said:

Thank you!

I have no idea what the existing feed is.

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The existing feed is the wiring from the existing elec. main service panel, be that the main service disconnect where the meter is housed or a sub-panel, to the dryer recepticle.

zannej said:

I'm thinking about this upgrade for my friend's house and for my own. My friend's breaker box is about 60' away from where he would install it and he can't really afford to buy new wire. I'll have to get him to look and identify what his current wiring is. It was a meth house that he's fixing up so it had all sorts of code violations and problems.

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Identifying that will determine a recommended course of action.

zannej said:

In my house, the outlet is just on the other side of the wall from where I want to move it-- I just want to flip it the opposite direction and flush-mount it inside the wall. The breaker box is maybe 10' away.

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Just make sure that breaker is off and marked, 1st.

zannej said:

Another question: If my friend installs a vent fan to get rid of moisture and doesn't touch the dryer outlet much (no unplugging unless it's an emergency or something) is it likely to be ok in a damp area? I'd suggest flipping the breaker to the dryer when people shower, but I don't think his girlfriend would remember.

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Although washer and dryers are housed together, the shower adds an additional "element of surprise", he'd be well advised to ground both appliances and if installing a vent fan, wire it to come on when the lights are on.

zannej said:

I really appreciate the responses. I'm hoping to gain a better understanding of wiring. That way I can at least spot when something is wrong if I see things or maybe correct issues with bad wiring in my house (although, I'll defer to experts and make sure it's the right thing before I touch anything electrical).

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Good Idea.

So in reading this, I'm not sure that the humidity/dampness question was addressed; does the dryer or outlet need additional protection because of shower steam? If not, then why not just provide the existing connection to the new location?

Zannej: I haven't read anywhere how he plans to vent the dryer in it's new location. he does have a plan, ........doesn't he?

slownsteady said:

So in reading this, I'm not sure that the humidity/dampness question was addressed; does the dryer or outlet need additional protection because of shower steam?...

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SNS this is one factor that I have never been able to wrap my head around when it comes to the laundry area in most dwellings (single family homes).

The washing machine receptacle must be GFCI protected because of the possibility of electrical shock hazard being in direct vicinity of a water source - the washing machine namely.

However, most washing machines have the dryer right next to them as a set. The plug/receptacle for the dryer is not 120V but 120/240V but is not required to be GFCI protected even though it is in the direct vicinity of a water source - the washing machine. If the body of the washing machine ever because electrified because of a loose hot wire the ground of the washing machine is supposed to enable to amperage to go back to the panel and the GFCI provides the protection it needs to. But in theory what happens with the dryer. What happens if there is a water leak of one of the water hoses (hot/cold) on the washer. If is sprays water all over the laundry area then would it not make sense for safety to have the dryer protected also by GFCI.

Lots of 240v installs seem that way. In my garage my welder plugs into the common welding outlet 3 prong and it’s in a garage area with moisture etc. I turn it on and off at the breaker panel before pulling the plug but nothing says I have to.


Wells run 2 wire and are connected to all the plumbing.


I just ran a service for a water heater for her granny. It was a deal where the power company gives you a free 80 gallon tank if you agree to be on the peak shut off program. The power company wouldn’t add the breaker or do the feed wire but would install the tank and do the plumbing as strange as that sounds. I ran 10-3 / ground. My white both went to the same place in the panel and the green and white both went to the ground lug when the guy hooked up the tank end. No GFCI and it sits right next to this water pump in a damp basement.

afjes_2016 said:

SNS this is one factor that I have never been able to wrap my head around when it comes to the laundry area in most dwellings (single family homes).

The washing machine receptacle must be GFCI protected because of the possibility of electrical shock hazard being in direct vicinity of a water source - the washing machine namely.

However, most washing machines have the dryer right next to them as a set. The plug/receptacle for the dryer is not 120V but 120/240V but is not required to be GFCI protected even though it is in the direct vicinity of a water source - the washing machine. If the body of the washing machine ever because electrified because of a loose hot wire the ground of the washing machine is supposed to enable to amperage to go back to the panel and the GFCI provides the protection it needs to. But in theory what happens with the dryer. What happens if there is a water leak of one of the water hoses (hot/cold) on the washer. If is sprays water all over the laundry area then would it not make sense for safety to have the dryer protected also by GFCI.

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Real good point, and worth thinking about.
But what about steam? I would think there is no threat from shower steam as it doesn't affect 120V outlets or fixtures in every bathroom in America. So why bother converting from 3-prong to 4-prong when the dryer is already wired for 3-prong?

actually 4 prong is safer as it provides for a separate ground. Loose hots touching a metal case such as a dryer, leaning against the dryer to pull your clothes out, feet firmly on the floor and touching the bottom of the wash-bin; ouch!!

Happened to me with my 3 wire stove. Had one hand on a large metal spoon stirring a pot of food. Metal spoon touching bottom of pot. Other hand reached to kitchen sink for something and touched the metal sink brim at the counter-top and "zing!"

Next day pulled the stove out and took back panel off. No strap from ground (chassis) to neutral lug; oups, took care of that right away.

slownsteady said:

So in reading this, I'm not sure that the humidity/dampness question was addressed; does the dryer or outlet need additional protection because of shower steam? If not, then why not just provide the existing connection to the new location?

Zannej: I haven't read anywhere how he plans to vent the dryer in it's new location. he does have a plan, ........doesn't he?

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Since he is moving the dryer to an exterior wall, he will put a hole in the wall behind the dryer and vent it. I am trying to talk him in to getting a cheap wall-mount vent fan to push moisture out of the house (mounted to the exterior wall) since he has no attic access and his ceiling is made up of a bunch of thin wooden slats that look like the rolltop part of a desk or bread box.
I will have to confirm that he has a GFCI outlet for the washing machine that is properly grounded. Would it be a 20amp?
I may dig in to my funds for my own reno and pay for the wire and fan for him if he can't afford it, and I believe I already have a dryer vent ducting kit in a box somewhere.
I'm still nagging him about doing the plumbing for his washing machine properly. If I could fit my fat behind under his house easily, I'd be tempted to go over there and fix the standpipe (he put the trap under the house against my strenuous objections). But, my main concern is that nobody gets electrocuted so I want to make sure he has the proper wiring and outlets for the appliances and some way of mitigating moisture build up. Secondary to that, I'm trying to convince him to put another layer of plywood down across the joists at least underneath the appliances because he only has one layer and I'm afraid it won't be sturdy enough.
I believe his existing connection for his dryer (in the adjacent room) is only 3-prong and I would like for him to get the 4-prong kind. I'd actually like for him to get a newer dryer, but that costs $ and he's pretty much broke bc things keep breaking.

TL: DR? Yes, he has plans to put a new dryer vent in the wall and his old dryer power outlet is not as safe so I think he should get the 10/3 ground to replace 10/2 ground (if he even has 10/2-- that place is total clusterf***).

Editing because I was typing this while afjes was posting. Not sure how to quote his post for this, but the 4-prong being safer is exactly why I want him to change it and why I want to use 4-prong for my own dryer when I remodel. When I was researching, I read that 4-prong was safer. My friend already got zapped very badly before working on something for his grandparents. He wasn't able to drive for years because it left his feet and right hand numb. He regained sensation in his feet, but still doesn't feel much in his right hand. He's got terrible luck and I don't want want to chance anything.

afjes_2016 said:

Next day pulled the stove out and took back panel off. No strap from ground (chassis) to neutral lug; oups, took care of that right away.

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So it wasn't really the three wire feed but an improperly installed stove that was the issue.

Stoves should be 4-wire now, right? 8/3 plus ground for 40amp?

Yes i do believe that's right.

Thanks. My friend needs to run some wire for his stove as well. His kitchen doesn't have a stove and doesn't have the proper wiring for it (his kitchen is smaller than the bathroom and just barely fits his refrigerator). So, he needs at least 50' of the 8/3 w/ground for a stove and about 60' of the 10/3 w/ground for his dryer.

zannej said:

Thanks. My friend needs to run some wire for his stove as well. His kitchen doesn't have a stove and doesn't have the proper wiring for it (his kitchen is smaller than the bathroom and just barely fits his refrigerator). So, he needs at least 50' of the 8/3 w/ground for a stove and about 60' of the 10/3 w/ground for his dryer.

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The distinction needs to be with the appliance's KW rating, if the runs are in romex or metallic conduit and the conductors are copper or aluminum.