Is the red wire the ground?

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O C Diver

Guru
Joined
Dec 16, 2010
Messages
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Location
USA
Vessel Name
Slow Hand
Vessel Make
Cherubini Independence 45
So my buddy bought a used boat last year. I'm not posting names, make or model.

The air conditioner was old and basically dead. He bought a new one and did the install today. My buddy is mechanically inclined and this wasn't a challenge until he got to the wiring. I get a phone call. Can you help me with the wiring? The power feed from the panel has a black, white, and red conductor. Does the red go to ground?

No, there's no way anyone uses a red wire for ground.

I'm going to send you a picture the way the old AC was wired.
2719.jpg

You have got to be kidding me! :facepalm: It sure looks like the red is the 120 VAC ground. Send me a picture of the back of the breaker panel, neutral buss, and ground buss.


Ground buss is bottom row in the center.
2717.jpg

:eek: Apparently this wasn't the previous owner's handiwork. This was wired by the factory this way. If you enlarge the photo, they paired up the red wires and put each pair in one crimp connector. Wonder if they had to cut some of the strands to get them both to fit in the same crimp? Seems some of the black and all the white wires were done this way also. :nonono:

Ted
 
Red is not a hot wire for ac. black is line , White is neutral. Red in this case could be ground. Installer may not have used correct wire in the beginning
 
Oh boy, it is a very neatly done mess. I think that if it was my boat I would be spending a week or so ringing out a bunch or wires. If indeed the red is being used as a ground wire, then I would get some green tape and tape both ends of the wires green so that it is obvious what the wire is functioning as. Then there is the bus bar issue, a lot of red wires on what looks like a ground bus bar, more ringing out the wires and taping them green. I would definitely audit all the wiring in the boat. Are you sure you don’t want to give us a hint who made this boat (mess)?
 
That is a 220v circuit where the black wire is one leg of hot, red is the other leg of hot and white is neutral. There is usually a green wire for ground.

I think you need an electrician to help you wire it. Your new A/C needs to be 220v.

David
 
That is a 220v circuit where the black wire is one leg of hot, red is the other leg of hot and white is neutral. There is usually a green wire for ground.

I think you need an electrician to help you wire it. Your new A/C needs to be 220v.

David

He mentioned 120v . You are right if it’s 220v
 
Yes, he said it is 120 volt. I agree he needs a marine electrician.
 
Color blind installer mixing green and red? :)

Note about two wires in one crimp, I saw some crimp terminal where you can put two wires, you twist the two together and they go in the crimping area while the plastic protection can contain two wire side by side, not sure I am clear in my description...

L
 
Put a meter on the wires and see what you measure across each pair.

Google old model for manual or wiring diagram and/or terminal labels and see how it was wired.

With luck the the expected wiring and your measurements are consistent. You can label the wires wires, use colored heat shrink tubing or tape at the ends to color code them, replace them with the right color, or kick the can onbthe coloring and just hook it up.

But, I'd want to see what the old AC claimed to be, verify I that book learning matches reality, make sure it is the same as the new (110v vs 220v vs 240v), and then, if compatible, hook up from there. If it was me, and the wire used the wrong colors but was otherwise correct, I'd likely heat shrink an inch or two of the right colors onto the AC end.
 
That is a 220v circuit where the black wire is one leg of hot, red is the other leg of hot and white is neutral. There is usually a green wire for ground.

I think you need an electrician to help you wire it. Your new A/C needs to be 220v.

David

So you think all those red wires are hot, supplied off the same common buss, without breakers? No, this is all 120 VAC. New 120 VAC air conditioner fired right up. I believe the boat has two 30 amp shore power cords and no 220 volt breakers. You can see green wires at the top and bottom of the ground buss. They are most likely from the shore power feeds and the generator.

The thread was more of a comment on a manufacturer failing to follow a basic industry standard wire color code and some really bad wire connector practices. I haven't been on this boat yet, but am told it is in good shape. Don't know if wire color is something that a surveyor would note, but he clearly missed the connectors.

Ted
 
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That is a 220v circuit where the black wire is one leg of hot, red is the other leg of hot and white is neutral. There is usually a green wire for ground.

I think you need an electrician to help you wire it. Your new A/C needs to be 220v.

David
BTW, 220 VAC circuits to a single piece of equipment (like the air conditioner) don't have a neutral. A shore power supply cable does because there will be 120 VAC circuits run off the panel that will require a neutral.

Ted
 
I am not sure what type of boat this is. And I am not sure if some of that wiring was after market. But most of the wiring that I have seen come from quality boat makers have ring terminals on their ends. And for some reason the crimps don't look like they were done by good commercial electrical tools.

Of course I have seen oriental boat manufacturers in the past have multiple wire colors in one lead from one end to the other. They used what they had instead of getting a new roll or wire just they needed more length of one color that's run out in the process of wiring some component. And there are two different colors on the same lug. So this tells me anyway that this was not done by any qualified electricians.


And a passing story from the orient was that when one guy went on a break another person walked in and continued work on the same job. So who knows either.
 
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On my old cruisair, 120vac 16k btu, the red wire is hot for the water pump.
The water pump connects to that red wire, and the big white wire is neutral return for water pump, compressor, reversing valve.

On mine are 4 wires in the sheath,
10 gauge purple is hot for compressor only.
10 gauge white is neutral
16 gauge red is hot for water pump only.
16 gauge blue is hot for reversing valve (heat to come on) only

Perhaps the green wire in the white sheath is not being used as the ground wire. Maybe its turning on the water pump. On my unit, a split system, the ground to the compressor is through the copper tubing. But a ground wire does exist at the three knob control panel.
 
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On my old cruisair, 120vac 16k btu, the red wire is hot for the water pump.
The water pump connects to that red wire, and the big white wire is neutral return for water pump, compressor, reversing valve.

On mine are 4 wires in the sheath,
10 gauge purple is hot for compressor only.
10 gauge white is neutral
16 gauge red is hot for water pump only.
16 gauge blue is hot for reversing valve (heat to come on) only

Perhaps the green wire in the white sheath is not being used as the ground wire. Maybe its turning on the water pump. On my unit, a split system, the ground to the compressor is through the copper tubing. But a ground wire does exist at the three knob control panel.

The green wire in the white cable is a ground. The white cable is power to the inline 120 VAC resistance heating element.

Ted
 
The green wire in the white cable is a ground. The white cable is power to the inline 120 VAC resistance heating element.

Ted
Well then, it looks like that red wire on left is connecting to the green-blue wire on right. With hot and neutral above.

There is a second sheathed bundle of 3 wires, looks like another hot - neutral - ground arrangement, but with a black wire connected to the green-blue ground.
That green wire looks somewhat blue.

Is that something he did trying to figure things out, wiring up that way on that terminal strip in the first pic? And the second pic is OEM?

The first pic, where is that terminal strip at the AC unit?

Everything has to be mapped out as to wire functions to understand how it is supposed to be wired up. A digital meter with wire ends disconnected so things cant try to start running, then someone turning switches off and on should be helpful in seeing what wire gets powered up and when.

If you know what wires are what on the AC unit, and can figure that out on the boat end, then they will match up function for function. Definitely cant ever go by colors as this boat has some odd arrangements.

The double red wire crimps, that is a 12vdc ground and AC grounds? may have opened the crimp larger to force fit, or it may have been a 10 gauge ring terminal which could take 2 wires.
 
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The first picture was from the original air conditioner. He has replaced the unit and removed the inline heating element. The new unit only required the power supply cable and the water pump power cable to be hooked up. Once the color coding was figured out, it was pretty simple.

Ted
 
It appears to be an older Grand Banks 49...that panel work looks very familiar. I will tell you that on the GB 49 I worked on about 6 years ago, we found 4 different colored wires butt spliced together in one branch circuit run!

The absolutely only way to to this properly is to disconnect the conductors at both ends and ring them out. Once L, N and G are identified, use heat shrink to properly color code the conductors at both ends. Better still, pull in new wire!
 
Not a Grand Banks.
There seems to be some consistency in the 120 VAC wiring. Red for ground seems to be a common theme. Probably not realistic to rewire as many wire runs are probably secured through inaccessible areas..

Ted
 
Ted: This looks like proper UWYG (use what you got) standards. The board looks like a DeFever or Monk, but probably built during a shift change.
 
Nope, not a DeFever or a Monk. It's got a pair of 3208 cats.

Ted
 
I have a 34 year old trawler with 3 120v AC units on it. I can tell you that the colors going to the control unit of the AC on all 3 do not match each other in terms of color. With that in mind, best to either call someone that can trouble shoot it for you to be safe, or put a meter on them to see what is going on.

Good luck
 
Those cables coming through the pressboard like paneling and taking a hard-over 90 do NOT look like ANY manufacturer original wiring I have ever seen, even on this miswired and wonky beast of mine. I would eventually correct all that color coding error with NEW wire - I WOULD!
 
Even if you don’t replace the wiring, when you figure out which wires are which, I would put proper color coded heat shrink over each end of each wire. It will help tremendously in future troubleshooting.
 
rgano #23:
I have seen many Chinese built trawlers circa 1970/1980 with exactly this configuration.

Not unusual.
 

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