Do you have to remove the plug to get all the water out of the hot water tank?
Yes.
Make sure you relieve the pressure before taking the anode plug out!
I forgot once and that threaded cap & rod blew out of the tank with surprising force. I was lucky as it could easily have hurt me. Also thankfully the water wasn't hot because as the plug rocketed out so did a six gallons (?) of water! I was soaked. It would have been burns if it had been scalding.
I just open the hot water drain valve by the sewer dump valves, open all the hot water taps, tank drains that way. I leave the valve open on the ay home and the tank is always empty. I have used this little trick for 30 years.
[font size="3"]Works much better if you open the COLD water low point drain along with the HW and all HW and CW faucets. The hot water output on the Suburban WH is at the top so it won't drain completely by gravity. The cold water inlet is at the bottom.
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