When should I set my temperature?

Start it just before you leave, and put it on cycle mode. It'll chill to proper temp, then only kick on to maintain.

Also, it won't be 85 overnight, so it won't be working as hard to cool.

 

Yes

 

I'd put it at -10 (at some point) until you get to the dock. That way you don't run the risk of them looking at it and seeing +5 and saying "we'll check later after we load the next truck. We need to see -1 or less".

It happens.

 

If you've opened the doors since turning it off last it may have a lot of humidity to remove via automatic defrost cycles. You prefer not to pull into a gate immediately following a defrost cycle, before it's had a chance to cool back down.

 

That's fine I guess unless you're the one paying for the hours time and fuel.

Some reefers are set to where they won't operate in Continuous Mode that cold. If that's the case then you would then set it at say 30 overnight (continuous), then crank it down when you head to shipper. Won't take long to get a dry trailer from 30 to 0