Smoke detector goes off in middle of night

Most smoke detectors have a 5 year lifespan (date of mfg is on unit). If that's not the case then I would just swap in a new one as they are inexpensive but very important to have a working one (or more).

I had issues with the CO2 sensor since new. Never the fire alarm. Finally had to disconnect.

Is it just a smoke alarm or also a CO2 sensor?

Are your windows open if so any campfires near by? If so wind blowing smoke in the trailer will set it off. Has happened to me several times

It is the alarm going off not the chirping the actual alarm which is very loud. We did take the battery out of it but it very disturbing to our neighbors.

Whenever I replace a detector battery I also use use a can of computer air to blow out any dust particles that might be on the sensor.

Replace the battery---those chirps could be your signal.

Since you said that your trailer is, "brand new," I might guess that your furnace has turned on and that the new furnace is burning off the manufacturing oil coating on the sheet metal and other parts...this produces an odor and can set off the alarm....it has happened to us..

It should stop after a couple of furnace cycles...

Friends have a 2015 fifth wheel and theirs is VERY sensitive to humidity. It will go off if you open the front door and leave it open for several seconds, like for carrying in/out dinner plates, etc. They cannot figure out how to address it other than to just ignore it and keep the doors closed.

We had the same issue with our smoke detector in our Fuzion. The only way we could get it to stop the beeping was to disconnect it. We could never track down an issue with it, it was wired into the trailer wiring, and had a battery backup. Everything had power but it still beeped.

Or are you talking about the smoke detector going off, and not just the beeping?