Hi BrendaWendell,
Welcome to the Heartland Owners Forum and Family. We have a great bunch of people here with lots of information and all willing to share their knowledge if needed.
The switch on the monitor panel is for propane (gas) operation, the switch with the red handle on it is for electric operation. Normally you do not need both on, but will heater will recover really fast like that. You need to check outside on panel for access to water heater, there is a small switch, usually with a pin through it that must be removed, and turned on for the electric to work. The inside switch will be the master switch then and you do not need to use the outside switch....But you must make sure the heater is full of water before turning on the electric side, it will burn the element out immediately. Next,, if everything is OK there,,,you need to make sure the outside shower and also inside shower are turned off at the control, not the shower head. Water will bypass and you will only get warm water. If this is all OK,,, make sure the bypass valve setup on the back of the water heater is correct... if the middle valve is open you will only get warm water also...
Several things to check, but let us know what you find.
Jim M