Interior Lights Dim on 15a No Battery

[DKeat]

Just picked up my first Travel Trailer!
It’s a 2006 Keystone Zeppelin 303. I’ve been making plans to inspect and repair over the winter and ran into an electrical question.
When I have the 15a adapter on my 30a cable to plug into our 15a outlet, if the battery isn’t connected, DC items don’t work properly (lights are dim, can only have 1 dim light working).
I’m getting 113v in the house outlet, 113v in the power Center and adequate voltage in the trailer outlets (around 113 I believe).
My converter shows 14.6v DC when battery is disconnected with the polarity fuses are out, and I believe 13.6v with the battery connected.
I’ve tightened the negative DC wire and all other wires in the terminal strip in the power center.

My questions are am I supposed to be able to run DC items with no battery on 15a? If so, could there be a wiring issue I’m not aware of?

Thanks!

[flybouy]

You should not run without a battery. The trailer is engineered to have a battery. Do not, under any circumstances run the slide without a battery. I'm guessing the lights have incandescent bulbs so running them can add up the amperage draw.

[DKeat]

Thanks flybouy!
The power Center manual has this as part of their process flow for diagnosing which made me think it was designed to work without a battery, and that something might not be working right:
“Replace the polarity fuses. Then disconnect the battery. Apply load to the system by turning on DC ceiling lights or other items. Do DC items come on and function properly?”

Just trying to make sure everything is working as it should while I fix it up

[flybouy]

The converter doesn’t know if you're plugged into a 30 amp or a 15 amp outlet. From your voltage reports I'd think the converter is ok. If you are running the slides, or the furnace they are high amperage loads that need the battery to provide the initial surge of the motors starting.

[DKeat]

Thanks again!

So it sounds that likely I’ll be able to run DC items with my battery hooked up, and if I have guests come stay in it in our yard before I get our 30a wired at the house, the 15a will charge the battery as needed when it’s used for any DC items.
I know on 15a I likely couldn’t run the AC, but just glad to hear it sounds like the power Center is working as it should
Appreciate the info!

[flybouy]

With the camper plugged into a 15 amp outlet it should keep the battery charged, operate the fridge on 120v ac, watch the television. Running the water heater on electric may be ok if the battery is charged and not putting a heavy demand on the converter. DO NOT RUN THE AIRCONDITIONER ON 15 AMPS.

Leave it plugged in to keep the battery charged and check the water level in the battery every 4 to 6 weeks. Top off with distilled water only. I would recommend changing over incandescent buls to led and invest in an EMS (energy managment system) and not a "surge protector".

[DKeat]

Thanks again!
Really appreciate you taking the time to explain all of thus.

[MarkEHansen]

Also, if you're using one of those cheap "hockey puck" 15A adapters, throw it in the trash and get a good "dog bone" adapter, like this one:

https://www.amazon.com/Camco-Dogbone.../dp/B000BUU5YA

Those little hockey puck adapters will melt with use.