First of all, the tee shown is not a sediment trap. In order to be considered a sediment trap, it must have a 90* vertical axis so the leg functions as a trash can using gravity.
That pipe must be protected from the element such as painting or wrapping.
The pipe is inadequately supported.
The issue of sed. traps outdoors is controverial. Some AHJs prohibit it fearing condensate freezing while others don't see liquid condensate but do see particulate foreign matter that does get catch in the traps. The code just says all gas utilization equipment must have sed. traps except fireplaces.
Up here most units just have the ptrap off the condensate dripping onto the roof. Sometimes a patio block will be put under it to dissipate the water so its not constantly hitting the same point on the roof.
Same here. Just pipe it out onto the roof appropriately to meet the manufacturer requirements and nothing more. From time to time the customer or we run a longer drain to a particular point for various reasons. 99% are like the unit pictured in this thread.