Question about winterizing

[Acosta1977]

Hi guys, new to this forum. Live in ontario canada, and aproaching my fav time of year (not), i bought a trailer this year, had it dewinterized at the dealer, drove it to a storage grounds, and never got around to using it due to rough year, anyhow, was wondering if it needs to b winterized, since it was never used, their shouldnt b any liquid in the tanks im assuming, unless the dealership leaves liquid in their when dewinterizing. Should i winterize? And if so, where can i get specific instructions for my particular trailer (jayco jayflight slx bhs242). Sorry for the long story.

[GHen]

Search for winterizing in this forum, lots of discussion around the topic.
I Make sure the trailer is level, open water tank drain. Open low point drains, they will have two valves, one for hot another for cold. I have them in two locations.
Open all water valves, sinks, shower, outside shower, toilet.
Drain hot water tank.
Then I have a attachment to hook air compressor to water intake, water valve all need to be open, don’t want to blow a seal out with air pressure. You just want free flowing air going through system.
Turn pump on and off to make sure no water is left in the pump.
Pour some rv antifreeze into all drains, just enough to fill p-traps.
Since it only gets to 20 here, that’s all I do.
In very cold areas you should add RV antifreeze to water lines.

I also keep refer open, keep a roof vent partially open, turn on dehumidifiers. Open awnings on sunny days to dry out and prevent mold. Check regularly for water leaks on rainy days.

Did I miss anything?