Have no hot water pressure in home

Try connecting a hose to the drain spigot at the bottom of the tank, open spigot. Did you get good pressure and was there a lot of debris?

My hot water tank is in a lock out mode fvd failure do I need to buy a new sensor

Hart, if you have dialectric unions on top of your water heater, unscrew the union and check for blockage on both inlet and outlet. This is most likely the problem. Please let us know what you find.

dscamper, if you are asking about the flame senser on a side vent water heater, just clean it with sandpaper and see if that helps.