If there is no hot water or the supply is not adequate or is too hot, check the upper thermostat. If the thermostat is busted, it should be replaced. Lack of regular maintenance can cause issues even though the thermostat is working because of sediment buildup. To fix this, flush your water heater.
Beside above, how do I reset my hot water heater?
Somewhere on your electric water heater, you’ll find a reset button. It’s usually red and often located near the thermostat. It may also be hidden behind a removable metal panel on the unit—and then behind some insulation. Once you find the button, push and release it.
One may also ask, why is my hot water not working but my cold water is?
If you have good water flow (“pressure”) at hot water faucets, but it’s cold, then the water supply piping is not blocked and the problem is in the water heater itself, or in a mixing valve.
Why is there suddenly no hot water?
A water heater that produces no hot water may not be getting power, may have a tripped limit switch, or may have one or more failed heating elements. First, check the water heater’s circuit breaker in the service panel to make sure it hasn’t tripped. If the breaker has tripped, switch it off, then switch it back on.