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Newell Gurus would like to thank Boomer for joining us.

amp question
Hello Gurus,
I have a question/issue I'm trying to figure out. 

One amp meter in my coach is reading almost 30 amps when I run my back AC, but when I put a meter on it at the AC (roof), it shows about 14 amps. The other meter for the front air is reading about 21 amps, but is also pulling about 14 amps on a meter at the AC. 
When the AC's are not on, I'm not seeing much pull that may be adding to it. 
Not sure what may be bad, the meters, the AC's or something in-between. Previous owner had some trouble with the rear AC tripping the beaker. He replaced the breaker a couple of times. 
I am a bit concerned and any insight will be much appreciated. 

81 Classic 

Herb, Harmony and Izzy
1981 36ft - VT-903
Hi Herb,

To keep from making false assumptions, how many roof AC units are on the coach?
Do you have an electric water heater?

You are on the right track in taking the measurements. 14 amps sounds about right for a singular running AC unit.

Do you feel comfortable pulling the cover from the main circuit breaker panel and taking the same current readings for the wiring connected to the AC breakers? If that reads around 14 or so, I would then measure the main legs coming into the breaker box, or the transfer switch if that is easier. If they read 14 or so, then your front meters are kaflooey (techie term).

As a sanity check, you could kill all the breakers to the AC units and see what the up front panels are reading.
Richard and Rhonda Entrekin
99 Newell, 512
Subaru Outback Toad
Inverness, FL (when we're home Cool )
I have 2 roof units. I do have a water heater. I have it off. I thought the AC was fried and was ready to replace it. Upon checking it out I was told by a tech that my magnum runs through that back AC breaker. I'll need to confirm. He thought that was not the best set up and should be moved off that breaker. I am electrically challenged so I'm trying to learn quickly, but stay alive.
How (long) or if at all could it run 30 amps on a 20 amp breaker? Seems dangerous.
I'll give the panel test a try. I don't have a transfer switch. I have an old fashion plug for gen.
Hopefully I'll be able to tell which legs is which. You said take measurements on wires coming in to AC breaker, then main legs coming in. Are they easy to tell apart?

Many thanks!
Herb, Harmony and Izzy
1981 36ft - VT-903
You can't pull 30 amps through a single 120v 20 amp breaker unless the breaker is defective. I have texted you, Herb.
Michael Day
1992 Newell 43.5' #281
If you pull the cover off the breaker box, you will see a singular wire attached to the breaker. You should measure the amperage on that wire.

Now look at the MAIN breaker for the entire coach. You should see two wires attached to that breaker. One black and one red. Those are the two main legs. Measure each with just the AC’s running. The neutral leg is white, and the ground is green. You do not need to measure white or green.

Caution is the watch word. You are working with live voltage. Do not do this if you are not comfortable. Find a tech or friend who is.

Early in my coach days, I found a basic “how to wire a house” book was a huge help in understanding the basics of how a coach was wired on the 120 side. Learning the fundamentals of 120V wiring is a worthwhile endeavor for any coach owner.

When you open the breaker box cover, take some pics and post them here. Identify the AC breakers with a piece of tape or something.
Richard and Rhonda Entrekin
99 Newell, 512
Subaru Outback Toad
Inverness, FL (when we're home Cool )

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