1st time trailer owner, question regarding battery/power

You have 2 electrical systems---120V AC and a 12V DC

Shore power (or generator) provides the 120V AC power via the power cord.
You have an AC Power panel with Circuit Breakers (Main breaker--30A and then individual 20/15A breakers) Individual ones feed---A/C Unit, water heater electric element if it has one & outlets.

The 'Converter' is feed from the 120V AC system....either via circuit breaker or plugged into an outlet.
With 120V AC power supplied the converter will provide the 12V DC power and recharge/maintain charge on trailer battery.
W/O 120V AC power the trailer battery will supply the 12V DC system

Need to find/open AC Power Panel and check all circuit breakers (turn them OFF then back ON)
DC Dist System is typically part of that AC Panel........converter is behind.
It has to have AC Power to provide 12V DC. If it is working you can measure 13.2V DC on battery cables were they are connected in DC Dist. Section.

If less than 13.2V DC then converter is not functioning properly.

New battery.......make sure it is connected correctly and not reversed.
Trace which cable goes to trailer frame...that is Negative cable. Colors of cable don't always make sense. If connected backwards you can blow the 'reverse polarity' fuses (30a or bigger) on the converter


AS stated.
You need good 12V DC to operate Water Heater propane (and electrical on Atwoods), Furnace, Fridge, Thermostat for A/C, lights, water pump, ceiling/exhaust fans etc.

Sorry just at work at the moment.
The battery is still connected. For a brief moment, when i went to the bathroom which has the battery/water guages, it lit for a matter of a second.
There is no AC in the unit.
Plugged in, the only thing that works is the microwave. Fridge does not (havent tried using gas on it), no lights, no stereo, no fan. I turned on the red switch by the sink, i assume thats for the hot water tank?? and it did nothing as well.

Check your fuses. It sounds like the fuse for the converter may be blown and you may have some other fuses blown. I bought my travel trailer used and the guy had no idea why the 12v stuff wouldn't work. Turned out is was just the converter fuse blown. When you say nothing else works.....does the ac unit kick on? When you first put the battery in did the lights come on? If it's been a little while since you put the new battery in they it may very well be drained already. Put a battery charger on the battery and see if it is drained. I think it would be helpful if you could identify exactly was DOES and DOES NOT work appliance wise. It could be narrowed down pretty easily that way.

Is the bad battery still connected?

I tried to charge the battery... which did not work. I havent had a chance to purchase a new battery yet no.

Did you put in a new battery?

Is it connected propperly?

NO! There are two completely seperate electrical systems in your trailer. 120VAC operates, air conditioner, one side of the refer, maybe the water heater. The 12VDC side supplies control voltage for the refer, furnace, lights. For the refer to operate without 120VAC power you also need gas (propane). Same for the water heater and furnace.

Thank you for the response. So, i have it plugged in. The microwave works, but nothing else. So would something be toast then?

There is no switch. You plug it in and providing the converter is working properly, you should have 120V & 12V to all facilities. When unplugged, you will have no 120V so therefore the microwave, Air Cond., and any other 120V appliances won't work. However all your 12V appliances like lights, water pump, refrigerator, etc. will work until the battery dies. Note, your fridge and furnace will work on propane with electronics powered by 12V; but the furnace fan will rapidly deplete your battery.