The answer to 'why is my garbage disposal no hot water' is that the garbage disposal and hot water are separate systems in your home's plumbing. The garbage disposal is connected to the cold water supply, not the hot water. If you're not getting hot water to the disposal, it's likely an issue with your home's hot water heater or the hot water lines, not the disposal itself.
Some common causes could be a malfunctioning water heater, a problem with the hot water supply lines, or a clogged or obstructed hot water valve. To troubleshoot, you can check the water heater, look for any leaks or blockages in the hot water pipes, and ensure the hot water valve is fully open.