Still have water heater issue.

Beaker wrote:

You have a bad check valve.

IF they have 3 valves, which husband says they have, there would not be a check valve.

Well top valve is open. Bottom valve is open. Middle valve is closed. Now no water at all coming out of the hot water taps. Cold water taps OK.

This though gives a thought that perhaps there is a check valve.
Has OP checked{by overflow valve) to see that there is hot water in the tank?