"Donna Ohl, Grady Volunteer Coordinator" wrote:

I was wondering why BOTH the hot water outlet and the cold-water inlet had
check valves built into the respective dialectric nipples provided in the
top of the new tank!

If you are talking about the galvanized nipples with blue plastic flaps that go
between the heater at the cold/hot ports, those are thermal breaks - not check
valves. They reduce the heat loss from the tank into the pipes when the water is
not being used.

A check valve is significantly larger than a nipple and would typically only be
be found after the main valve and before the heater.