exhaust elbow

A plumber installed a new tankless water heater today. My previous one crapped out and blew my exhaust vent across the yard. The plumber reset the vent birdscreen elbow faceing up toward the sky. Is that correct? Seems like rain water would get in and run down into the heater’s combustion area.

I purchased an AO Smith GDHE 50 from a local builders outlet store for $1000. I have it all installed with the exception of the exhaust. The condensate drains from the bottom exhaust port through a drain that I believe was supposed to come with the unit. Mine of course did not. I see an AO...