we are hooking up a new dishwasher and the house wiring has no ground wire. what should we hook the green ground to?

 

What type of cable contains the Branch-Circuit conductor that will connect to the D-W?--- Metallic, or Non-Metallic?

You will have a Grounding problem if the cable is a Non-Metallic cable without a bare Grounding conductor.

 

Hello: Fiestagal

Appliance grounding clamps are available at local hardware stores. Such clamps are used for the purpose you need.

The grounding clamps are grounded to the existing cold water line under nearby sink water line. Be sure to clean the outside area of the pipe before attaching the clamp.

Best option if possible but more costly would be to have a licensed electrican bring a ground wire to the electrcial box, change the box to a 3 prong recepticule and ground it to the main electrical panel.

Based on the question, as I read it, the above paragragh may not be an option at the time. The grounding clamp will solved the problem for now and most likely forever.

Problem is, if no ground wire is there in the electrcial box, not likely to be any in other electrical boxes either. Which means other large and small appliances are not likely to be grounded either...

A possible condition which would be best to check everywhere else. Washer and Dryer may not be grounded nor any other kitchen appliances. Caution would than be advised.

 

I'm not sure what that means??? the house wiring is what we call romex 2-wire. it's an insulated covering around the black and white wires. no ground in the middle.

 

thanks for that advise. you are probably right about the other wires. we are remoderling our whole kitchen and when we hooked up the new vent-a-hood, we had this same problem, but
we had help and i'm not sure what they did about that. is it a huge problem if there is no grounding wire? we have lived here 12 years and haven't gotten shocked yet??

 

Hi: Fiestagal

Yes. Older house did have two wire Romex wires when they where first built. Two wire Romex is a thing of the past. Not used anymore in any area I am aware of.

Rewiring is now done with three wire Romex, the new standards of today. The third wire is the bare ground wire already included in the new Romex wire.

That's how the ground gets from the main electrical panel to the wall recipticule box. Using the new three wire Romex wire. Which would need to be installed at the dishwasher outlet and all other electrcial appliances and wall outlets for power.

If you have not gotten shocked over the last 12 years, it is both luck and the fact that modern electrical appliances, regardless of how large or how small are built so well...

Pushing ones luck by not having electrcial appliances grounded is like playing with fire. Sooner or later, one will get burned. In your case and in my opinion, a shock is bound to happen sooner or later.

Be safe and be smart. Ground appliances per mfg instructions and have all electrical outlets grounded by a licesened electrical contractor in your area. Also an improvement to a house...

 

o.k. so i need to splice a ground wire to the green one on the d/w and connect it to a grounding clamp attached to the existing cold water line under the sink? is that right?

 

DO NOT CONNECT A GROUND WIRE FOR AN OUTLET OR APPLICANCE TO A COLD WATER PIPE.

This is bad and dangerous advice. It could create a life threatening problem. It also violates code.

You cannot ground anything in this manner.

The only acceptable and safe grounding manner is to run a separate ground wire all the way back to the panel, or to replace the original wiring with new wiring that has a ground.

DO NOT CONNECT A GROUND WIRE FOR AN OUTLET OR APPLICANCE TO A COLD WATER PIPE.

New NM-B cable has three wires. A black wire for hot, a white wire for neutral, and a bare ground wire. THe ground wire in Romex is not green, it is bare.

It is not dangerous to have ungrounded receptacle outlets. Most lamps and appliances do not need the ground wire. Ungrounded outlets should be the two hole kind, not the three hole grounded outlets.

Appliances such as washers, dryers, microwaves, computers, etc, do need a ground wire. This is because they either use the ground wire for reference, or because they have a metal outside surface and need to ground that surface.

Devices that use the ground for reference (computers), or for fault current (UPSs and surge protectors) need to be properly grounded. Ground these with said wire back to the panel or by installing new wire.

Devices that have a metal shell and need the ground for safety should be used on a properly grounded circuit, or they should be used on a GFCI protected circuit. A GFCI provides an alternate means of preventing an accidental electrocution, and allows use of grounded appliances on ungrounded circuits.

 

I stand corrected. My error. Correction noted in my prior reply.

Info provided was in fact incorrect. The third wire in the Ropmex for ground and is NOT green, as I indicated prior. It is bare. Correction noted.

Green wire should be one of the three wire colors in the dishwashers wire. If that is correct, great. If not advise me.

Grounding a washer is always adviseable. Applies to all appliances which use water. Last washer purchased around here provided grounding clamp in installation package kit. Not to worry, clamp not used nor needed. Box grounded...

That was just two years ago. Codes changed already? Advise.
State codes or federal codes??? Which codes and where?

By sharing we all learn more....

 

o.k. no ground to cold water pipe. got it. no bare or green wire in house wiring. so what is my other option? new house wiring is not an option. when you say "panel" do you mean breaker box?
how would you get a wire all the way back to there???

 

I found this information by searching on the web...

"NEC Handbook Due to changes in Section 250-81 made in the 1993Code, an interior metal water pipe more than 5 ft from the point of entrance of the water pipe into the building is no longer allowed to serve as a conductor. This revision was due to the increasing use of nonmetallic piping and fittings."

It looks like the 1993 code is where the change took place.

Tools and appliances with metal cases must be grounded or be double insulated. Insulated means that there is no metal connection between the outside of the device and the interior electrical components. Insulating on a large appliance is neither cost effective or easy, so on large appliances they ground the outside to the ground wire on the circuit.

The theory is, that if a fault occurs and the case becomes charged with 110 or 220 that it will, because of the ground, cause an overload of the circuit breaker and trip the breaker.

Thr problem with using a cold water pipe instad of an actual wire is that until the breaker trips, there is 110 or 220 volts at a large number of amps on the plumbing. Someone using the plumbing (washing their hands, taking a shower, sitting on the throne, etc) could get shocked, and it could kill them. This is especially true if there is a break in the copper pipe (because of a piece of plastic pipe, for example). The breaker may not trip and the plumbing will be "hot" and capable of shocking and killing someone.

Further, a small fault (such as one that draws a few amps or even less) won;t trip the breaker and will have the fault current running through the plumbing. Since electricity takes all paths back to the source, someone touching the plumbing will could pull some of that fault current through their body and cause fibrillation of their heart.

 

Yes, I mean a green wire (of the same gauge as the circuit wire, usually 12 or 14) all the way back to the circuit breaker panel or fuse box.

Is this a cord and plug connected dishwasher, or a hard wired dishwasher?

If cord and plug connected then you could install a GFCI receptacle outlet. A GFCI outlet won't provide a ground, but it will allow a grounded appliance to be connected and will provide electrocution protection.

Obviously the best solution is to have the wiring upgraded.

Note: If you are remodeling your kitchen then you most likely will have to bring your electrical up to code, which means replacing the wiring. No building inspector will allow old wiring to remain in a remodeled kitchen, unless you are doing very basic and simple remodeling.

 

How can the case become charged with 220 volts?

 

In this case, it couldn't get 220. But I was talking in general, and it is possible (although unlikely) that range, for example, could develop 220 volts between two different ppoints of contact.

 

Hi: Fiestagal

Good question. You asked "how would you get a wire all the way back to there???"

Based on the fact the box near the dishwasher is not grounded, the answer must be yes. You will have to run a ground wire all the way over to the main panel.

Main panel means the main electrical panel (Box) where the electric comes into the panel from the wires off the electric pole.

Based on the replies we both get here fiestagal, we both can learn more...

Questions for the pros:

Assumption I made in a prior reply... Older house with two wire system most likely does not have underground electrical utilities. Thus wires to a pole.

1)
Question than is, the existing panel fiestagal has at her house grounded at the pole through the bare return wire?

Prior assumption I also made was older house still has original piping which would not contain nonmetalic water piping.

2)
Unless repairs where made after the codes changed maybe?

3)
Replace a section of bad pipe with nonmetalic section?

4)
A Ground Fault Interrupt (GFI) okay to use when no ground available?

Correct me if wrong....we all learn more that way.

A)
If main power wires are to an electrical pole and the house still has two wire system, main panel box just may be grounded to inlet cold water pipe. It was done that way many many years ago...

B)
Not so in modern times. Now a grounding pole is attached to main circuit panel and griven into the ground right at the panel. Now done here in this area for all new contstruction and all retrofifts or rewirings.

 

o.k. first of all, my house is 30 years old, but it does have underground utilities. the breaker box is on the back side of the house, outside. as my dishwasher that i just took out did not have a wire running all the way to that box, i don't think that is the answer for me. what ever happened to connecting the ground wire to a screw somewhere on the main unit? or to a piece of metal?

 

two things,
1. the d/w is hard wired
2. there is no "box" near the dishwasher. i'm not even sure what that means. since i am not an electrician, i need more basic info, please.

 

For the case of this DW, does the manufacturer's instructions indicate that it must be connected to a circuit with a grounding wire? If so, then you must run a new circuit to your circuit breaker panelboard that has a ground wire.

You cannot rely on metallic piping unless it is the main water service, it is metallic and within 5' of it's entrance.

Most older system have some type of grounding electrode system, whether it is the water pipe or ground rods, as it has been required for many years.

Most electric services have a bare conductor that acts as the neutral and ground going back to the utility pole or pad mount transformer. Neutral and ground become two separate entities at then main disconnect (sometimes permitted in the meter cabinet).

 

Fiestagal

Both learning more...

House 30 years old and does have underground power lines into main electrical panel box outside house. Good that's cleared up.

Box is the term often used for an electrical wall outlet. The place where a vacumm, toaster, iron, etc for instances would plug into.

A wall recipticule where electric power is present so a plug in type appliance using electric gets plugged into. Hope that helps to clear that up.

I too have that problem of not knowing what all the techy terms are. Not to worry, you are not alone on that issue... Basic (laymens terms) is now the norm.

If the existing dishwasher is hard wired, that means it does not have a cord like a toaster for instance. In that case, according to the pros, a wire has to be taken front the main panel and extended to the place (outlet) where the dishwasher is.

Logic than indicates, neither you nor I would know where to attach that wire at the main panel. And doubt we can learn here in a text only format.

Thus, in my opinion, neither of us should be attempting to run any wire into the main panel? Makes sense? Thus take part of the job would be wise and safe to have done professionally. Agree?

Pros. What is your take? Should we or anyone like us be attempting to run a hard wire into the main electrical panel?

What is the chances we wind up electrocuted trying to fish and attach a wire behind the breakers? Seems high to me.

One error and ZAP, 220 hits us.

Fiesta needs a ground wire to the location.
What shall we do now? And How?

 

now, that's some "sharp advice" for sure. i think i will call an electrician to help me out. thanks, guys for all the input.