So, I learned something new today regarding low profile walk-in cooler evaporator coil drain pans (specifically ColdZone).
This is the style where the fans are on the bottom mounted in the drain pan, sucks air up the bottom and blows it out the sides.
Well, the screws holding the drain pan in cannot be longer than about 3/4". Because if you use a 1" screw it makes a bad hissing sound as you drive in the screw with your impact driver.
Luckily another tech was nearby to weld up the hole in the U-Bend and get the thing running again...and luckily the thing was pumped down and off when it happened so only 2 lbs of R22 were lost!
Surprisingly my boss didn't freak out; his words were "So did you learn something?"