On Friday, October 23, 2020 at 10:45:11 AM UTC-4, Retirednoguilt wrote:
You're at tremendous risk of carbon monoxide poisoning. I would turn off the gas supply to the water heater immediately and get the unit serviced (if feasible) or replaced today. Meanwhile, you can go a day or two without washing clothes or taking a shower. Dishes can be washed in the sink with cold water unless someone is very ill with a highly communicable disease, in which case, buy a small supply of disposable paper plates, cups, and plastic utensils

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I agree, it's the exhaust blower and if it's not working, I would turn off
the water heater until it can be replaced. I would think they must have an
interlock of some kind there to prevent it from firing if the blower fails.
If it doesn't have proper airflow it will generate CO.