Air conditioner size

Will a 13.5 AC be enough for a 29ft trailer?
Most temps under 100 but occasionally up to 105
thx

Depends on a lot of things. Is the TT in the shade or sun, how fast do you want it to cool off, humidity, wind, insulation of the coach, and how cool do you want it? I have been in the California delta at over 100 degrees in the sun (no shade) and 13.5 was able to keep the inside of our fairly well insulated 30 foot TT about 25 degrees lower than outside ambient. I don't think trying for more than about 25 degrees is realistic with a 29 foot TT and one 13.5 AC.