If you had the electric side of the WH on for more than a few seconds, the element most likely burned out. As mentioned, it is pretty easy to replace. You can get at some Home Depots. Opening the cold water side to get the air out will not fill the WH. If you choose to use a faucet to fill the WH, you need to leave hot water faucet on until a good stream of water comes out. This should take a few minutes. If water comes out fairly quickly after opening hot water line, either WH was full or is bypassed. Just an FYI. If you burned out the electric element and plug TT into a GFCI at home, it will trip the breaker.
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