Can the hotel kettle be disinfected with 84?

You can't. Disinfectant is toxic, there will be residues, and it will enter the human body with the kettle water, which is toxic. Clean the kettle with safe things such as edible vinegar. Generally, the water in the kettle is the scale left after boiling water, mostly alkaline. It can only be neutralized with acidic vinegar, so as to soften the scale and clean it up. When cleaning, pour an appropriate amount of vinegar, leave it for a period of time, and then wipe it with a coarse cloth after the scale becomes soft.