Is it acceptable to have the T/P valve at the top of the hot water outlet as opposed to the T/P valve port on the water Heater? I have come a crossed this in a couple occasion’s.
depends on tank manufacture some are top and some are side
Older units(in my area it is typically from the 60’s) with no built-in valve did often have the T/P valve installed in the hot water piping just above the furnace. The same termination requirements should be applied. If it is still present but a modern tank has been installed with a built-in T/P, I would recommend removal since it is considerably older and unnecessary.
TPR valves should be in the top 6 inches of the tank where the hottest water is found.