How to run both AC’s on 30 Amps . . .

or, Happy 1st Birthday to our grandson, Landon Thomas Morrison.

We both slept late this morning. Even Jan didn’t get up until about 9:30 and I followed about an hour later. Later, along with our morning coffee, we caught up on a bunch of TV shows from our DVR.

After lunch I set up the computer so we’d be ready to Skype Landon’s Birthday Party later this afternoon. We’ll just wait until they call.

Then I got back on my chore list. Since Jan planned on cleaning out some more stuff under the bed I thought I’d make my AC modification today.

A week or so ago I had a problem with the front AC not getting any power, but the circuit breaker was OK. After a call to American Coach I found out that the front AC passes back through the Heart Source Manager Inverter/Converter Transfer Switch through an AC Lockout relay.

Why, I don’t know. And I also don’t know why it suddenly engaged, even though the Source Manager is mostly disconnected due to my previous transfer switch problems.

Anyway, at the time, the solution was just to pull the wires off the relay and tie them together like below.

AC Bypass 1

This not only fixed that problem, but gave me the solution to another problem.

I had been thinking for a while about a way to break out the power leads to one of the AC units so that when I was plugged into 30 amps I could power one of the AC’s separately from the additional 20 amp outlet that most pedestals have.

I originally thought about tapping into the circuit breaker panel, but kept putting it off. But this seemed to be the perfect solution.

The first step was to replace the wire nuts with a set of male and female power plugs. Note that the end that supplies the power has the female plug for safety.

AC Bypass 2

This allows me to plug them back together to get back to normal.

AC Bypass 3

But it also allows me to plug the AC into an extension cord that I ran in through the bedroom window. The other end is plugged into the 20 amp receptacle on the power pedestal outside.

AC Bypass 4

This of course was only a test. I used it to run both AC’s all afternoon with no problems. Now I’ll run a permanent cord down through the engine bay and into the power bay. That way I can just plug in from outside whenever I need it.

This will probably only be used occasionally, Right now we only have 30 amps, but since the temperature is in the 80’s, one AC works just fine. But we have sometimes been in high 90’s temps and with only 30 amps available, one AC really can’t keep up.

So now you know how to run two AC’s on 30 amps. If you have any questions, let me know.

About 2:15 our computer rang and we were online Skyping Landon’s birthday party. Our signal quality varied a lot, so the photos do too.

The party started off with Landon opening his presents. Although sometimes he seemed as interested in the wrapping paper as to what was inside, he did a good job tearing everything open, And he seemed to be happy to find toys and other stuff inside.

Video call snapshot 233

Video call snapshot 236

Video call snapshot 237

Of course, after the presents, it was time for cake and ice cream. And Landon got his own cake.

Video call snapshot 266

And he dug right in and really enjoyed it.

Video call snapshot 270

Video call snapshot 287

Video call snapshot 288

We were online for the party for almost 30 minutes, and really enjoyed being included in the festivities. As a follow-up Brandi called about 5:30 to bring us up to date.

On another note, we’ve been noticing the first signs of Fall here. There is a slow but steady rain of yellowing leaves floating down from overhead. I’m sure everyone around the country will be happy with the cooler temps. I know we will.


Thought for the Day:

"It is terrible to contemplate how few politicians are hanged." – G.K. Chesterton



10 Responses

  1. I have been in Or., Wa. and Id. for 2 months and I am happy to be back in Ca. where it is warm and dry again.

  2. Greg, I am not the brightest bulb on the tree, I am more like Nick. I have a go to friend for all my tech questions … like Nick with you:) That being said, It would seem your arrangement to draw more than 30 amps from a 30 amp pedestal would cause problems backup the line. The wires running to the pedestal are for caring 30 amps. If you start pulling more than 30 amps will they over heat?

  3. The reason this works is that according to the N.E.C. (National Electrical Code) every breaker in a panel should be capable of supplying its full rated power and so should the wires feeding it.

    Just like the breaker panel in your Sticks & Bricks. the total feed amperage (usually 200 Amp) should meet or exceed the total amperage of the installed breakers.

    So if a pedestal has a 30 amp and 20 amp receptacle, it should be able to furnish a total of 50 amps. Just the 50 amp pedestals you find with 50, 30, and 20 amp receptacles can supply a total of 150 amps. The 150 amps total is because what we in the RV world refer to as a 50 amp hookup actually can supply 50 amps to each leg for a total of 100 amps. Note the breaker on a ’50’ amp circuit. It is two 50 amp ganged breakers, not just one.

    Another example is the hookups we’ve seen at some fairgrounds. I’ve seen pedestals where one pedestal supplies 4 rigs parked back to back. The pedestal has two 50 amp and two 30 amp receptacles. It’s first come, first serve concerning who gets what, but all 4 rigs can draw the full rated amperage.

    I’ve also seen pedestals like this with a 50, 30 and two 20’s, again first come, first serve. This pedestal should supply 170 amps as should the wires feeding it.

    Hope this makes sense. Let me know if you have any other questions.

  4. You are a clever guy, Greg. And you have a very cute grandson.

  5. You are a very clever guy, Greg, and you have a very cute grandson.

  6. Oops

  7. Greg, Thanks.

    I did not know about the code requirement. I assumed that the lower amp receptacle was there for convenience. This explains why some campgrounds and fairgrounds only have one receptacle (a 30 or 500. I just assumed that it was because they were too cheap to provide the lower amps !

  8. Thanks. I’m making sure Dave sees this power fix.

    Landon pix are good even when they aren’t. 🙂

  9. Camco actually makes an adapter that allows you to pug into a 30 amp and 20 amp outlet simultaneously, and then plug your 50 amp plug into the female end making your total available amps 50. I have one, and it works wonderfully, and requires no rewiring, or Rube Goldberg setups. Here is a link:

  10. Clarke,

    I looked at this awhile back, but according to this description from Amazon and also from, it will not work if the 20 amp outlet has GFI. Most I have found do have GFI, including the one I was using yesterday to test this out.

    From Camco RV Power Grip Maximizer 45 Amp Adapter gets up to 45 amps combined power with power maximizer. It draws the combined power from a 15 and 30 amp outlet, which allows the RV to receive up to 45 amps. This maximizer does not work when plugged into GFI type outlets. It is a polarized adapter designed solely for recreational vehicles and is not for use with any other adapter or device. This maximizer adapter must be used in conjunction with properly sized circuit breakers.

    The problem with the GFI comes from trying to combine the 30 amp and the 20 amp into one. The grounds potentials are different, thus triggering the GFI on the outlet.

    That’s why I wanted my set up to keep them separate.

    Thanks for reading our blog.


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