When you get your new trailer............READ ALL the manuals/pamphlets/brochures/information sheets etc.
Should be operating instructions for ALL appliances.....water heater, furnace, fridge, A/C Unit, converter, water pump....generic info on trailer etc.
Sit down inside trailer one afternoon READ and then go thru steps.
Also.....when you pick up your trailer and do the 'walk thru' Take notes/videos and ASK lots of questions.....make them show/explain. AGAIN if necessary.
It's your one chance to be shown.use it
The biggest advice concerning fridge........
LEVEL whenever operating fridge......even for 15 minutes.
OFF-LEVEL operation will KILL it faster than any other misuse.