Is it necessary to drain gas water heater when replacing water taps?
Not necessary. Turn off the supply and they’ll be no pressure to move the water out, then turn on the taps at the shower and let those drain. You’ll have air in the lines when you are done, so after the job you’ll have to go around and bleed the air out of the lines by flushing toilets and running water at the faucets in your house.
