Okay, so a few weeks ago went out to the TT to get it ready for a trip and my AC had died. I replaced with a new Dometic Brisk II and it seemed to working great at home. I had planned a 50amp upgrade from my 30 and did that yesterday. Everything seems to work, except that the AC doesn't kick on. Now, I'm only plugged into my house 20 amp circuit, but the AC always worked before on it with no issues.Is there some reason with the way that 50amp service works that my AC shouldn't work - is it somehow getting much less amperage?I have double-checked all the connections in the circuit box and everything is tight - even put a meter on the breaker to make sure it wasn't bad.I don't have a 50 or 30 amp source readily available to try, which is why I'm normally just plugged into the house wiring.

The odds are good that you wired something wrong. But see below.Is the A/C actually getting 120V power ?Is the thermostat getting the low voltage that it needs ?Then: Plugging a 50 amp vehicle into a 20 amp outlet may mean that only one side of the 50 amp service is hot and the other side is dead......and that would be normal.

Sam Spade wrote:Then: Plugging a 50 amp vehicle into a 20 amp outlet may mean that only one side of the 50 amp service is hot and the other side is dead......and that would be normal.Of course this isn't "normal" ... if one uses a 15 amp male > 50 amp female dogbone to plug a trailer properly wired with 50 amp main service into 15 amp or 20 amp service both legs of that 50 amp main service into the trailer will be powered, limited of course to a maximum draw of 15 or 20 amps across both legs, in which case the A/C, no matter which leg it's wired to, would receive power ... provided of course that this wiring the OP did was done correctly. ;)

You have the a/c on the hot leg your 20 amp is not supplying. That is just my guess. Do you have a dog bone 50-20 or how are you hooked up.

Do you have a fully charged battery to operate the thermostat correctly? A meter would tell where there is power and where there is none.Don't know exactly about your A/C wiring but some systems have a delay incorporated.

I guess you can use two RV adapters 30-50 and then a 30-15 and that should feed both 50AMP zones in your trailer from a 20A Recetacle from the garage area... Doing this of course you only have 20AMPS being divided up by all of your appliances in the trailer in both zones... You will have to turn off ONE Air Conditioner for sure to keep from tripping the 20AMp Breaker in the house... RV30-50 Adapter - Note the two 50A side HOTS are tied together here... RV30-15 AdapterRoy Ken

Upgrade to 50amp - now AC doesn't work | Good Sam Community

25 Replies

thebat68
Explorer
Aug 05, 2016
I would like to thank you all for proving my point.
myredracer
Explorer II
Aug 05, 2016
beemerphile1 wrote:
I've installed and worked in many electrical panels. Since changing the service from 30a to 50a would require replacing the electrical panel and relocating all the circuits I would not call it simple and certainly not a job for an average layman.

Agree. Not sure how he could have done it in "just a few hours" either if you also include time for installing new 50 amp romex cable from a new 50 amp panel to a new 50 amp power inlet on the outside (or even if it's a non-detachable cord).

Or maybe he just ran a new 20 amp circuit to plug into the 20 amp GFCI in a pedestal and kept his original 30 amp panel and created a "faux" 50 amp service? Would be interesting to hear details.
time2roll
Nomad
Aug 04, 2016
Tedious but by no means difficult.
Bumpyroad
Explorer
Aug 04, 2016
beemerphile1 wrote:
I've installed and worked in many electrical panels. Since changing the service from 30a to 50a would require replacing the electrical panel and relocating all the circuits I would not call it simple and certainly not a job for an average layman.

I think that most who did this merely used a 50 amp supply from post to new panel, then dropped a 30 amp off that to the old panel. didn't relocate a lot of circuits and ran new circuits to AC etc.
bumpy
beemerphile1
Explorer
Aug 04, 2016
I've installed and worked in many electrical panels. Since changing the service from 30a to 50a would require replacing the electrical panel and relocating all the circuits I would not call it simple and certainly not a job for an average layman.
westend
Explorer
Aug 03, 2016
thebat68 wrote:
Yes, I fixed it. It was a cut (or broken splice) in the A/C wire, so I had to run a new line. Everything is working great and now I have no power mngmt issues to worry about.
BTW, the 30 to 50 amp upgrade is one of the simplest things I ever done on my RV and only took a few hours. Like most things, it simply takes a logical, step-by-step approach.
That's great but you could share with others how you accomplished this upgrade. That would be along the lines of helping others, what most of the posters in this thread are about.

The flames start igniting when the details to what needs fixing are missing. It happens frequently and can be frustrating for those that have the knowledge and are just trying to share.

Good luck with your new electrical distribution.
thebat68
Explorer
Aug 03, 2016
Yes, I fixed it. It was a cut (or broken splice) in the A/C wire, so I had to run a new line. Everything is working great and now I have no power mngmt issues to worry about.
BTW, the 30 to 50 amp upgrade is one of the simplest things I ever done on my RV and only took a few hours. Like most things, it simply takes a logical, step-by-step approach.
Housted
Explorer III
Jul 03, 2016
TNGW1500SE wrote:
lawrosa wrote:
.......Very odd yes.. Why would one upgrade from 30 to 50 amp? ....

....I still wonder what happened to Tony Soprano.
;)

Tony is with Hoffa!!!

Housted
TNGW1500SE
Explorer
Jul 03, 2016
lawrosa wrote:
.......Very odd yes.. Why would one upgrade from 30 to 50 amp? ....

Well there's lots of reasons. I did it on my old TT.

Added a new panel & cord for the incoming 50.
Used the old 30 panel as a sub. (un-bonded)
Fed old from new using 30 amp breaker in new.
Moved the A/C from old to the new panel.
Added other circuits to the new panel for elect heat and elec cooking.

It solved all of the "power management" problems 30 amp had. You could run everything at the same time. No more tripping the 30 amp main.

So....I understand why he wanted to do it. I just don't understand how he did it. Since he doesn't return, it could be a sign that he doesn't understand electricity, he's in the hospital or worse. Also could be that he fixed it and just left us all hanging. The last guy I tried to help with an electrical problem called us all drunks and never came back. Some questions may never be answered. It's like one of those movies that leaves you hanging in the end. I hate those don't you? I still wonder what happened to Tony Soprano.
;)
gbopp
Explorer
Jul 03, 2016
Bill.Satellite wrote:
Could you tell us what you did to upgrade from 30 to 50 amp?

It would have been very helpful if the OP explained this when asking his question.