Originally Posted by Gunnyusmc
My problem is that if the A/C is running I can't use anything else. I have room in the breaker box for more breakers, but the trailer seems to need more amps in, as the A/C is on it's own breaker, but blows the breaker at the power source if I try to tun on the TV or anything else.
Although you can always run the 50 amp service you mentioned, you need to determine if you are treating a problem (not enough current) or a symptom (bad breaker or something's drawing too much current). A handheld, clip-on ammeter will make the following excersizes easier. Don't use the ammeter in your multimeter - it cannot handle the load.
The A/C is, I believe, on a 20 amp breaker. After it has started up, it shouldn't be pulling more than 15 amps. That should leave around 15 amps to run your other stuff. This makes me think the breaker at your power source is weak. Breakers do wear out over time. Let's say you ruled that out either by replacing the breaker or found the ammeter indicated close to 30 amps.
What's drawing the power? Must be the A/C. Breakers can also go bad by the contacts fusing together. I know - I have replaced one. This would be worst case. In means your A/C has a $problem$ in addition to the bad breaker. Failure to address that issue could leave your Airstream looking like Mr. Dummy's did in that Ebay listing
Let's say you ruled that out either by replacing the breaker or found the ammeter indicated less than 20 amps to the A/C. What else is drawing power? If your Univolt (or equivalent) is hardwired in, it shouldn't be pulling more than three amps. And you don't have an electric
water heater, right? Switch off all the breakers except the A/C, and check the current draw with the A/C on. Check the current at both the power source, and where your power cord hooks up to the 30 amp breaker. The current readings should be fairly close. If not, take the handheld, infrared thermometer you got when you purchased the ammeter and check temperatures along the length of your power cord. I use my "calibrated" hand, but you'll impress the heck out of the neighbors with your IR thermometer
Hopefully, one of the checks outlined above will identify the problem. Good luck, and please let me know your results.