This is a required post for the water heater training course. Attached pictures are of my water heater, installed by licensed plumber. No sediment trap in the gas line, no drainpipe on the pan and P&T discharge pipe is reduced in diameter.
What do you see?
It needs to be mechanically fastened in some manner and could use a insulation blanket. Otherwise, the 3/4" flex connecting into the half inch copper is an attempt at saving some time or costs. Should be 3/4" continuous. Looks like s garage so I’m not clear about the pan. Shouldn’t be required. If it is a garage it needs to be elevated 18" off the ground. Gas is heavier than air and could ignite if there’s a problem.