Follow the metal tubes from the bottom of the control box to where the tubes enter the tank. The metal panel on the side of the tank that the tubes pass through is the outer access panel. Pull the outer access panel off of the tank to reveal a second access panel.
Lift the second access panel away from the tank to reveal the pilot light and the tip of the thermocouple.
Shine a flashlight on the tip of the thermocouple inside the tank. The tip of the thermocouple must be positioned directly in front of the pilot flame. Bend the thermocouple's clip to reposition the tip of the thermocouple if necessary.
Light the pilot light by following the instruction sticker affixed to the side of the tank.
Observe the pilot flame to determine whether it extinguishes. If the flame does extinguish, a new thermocouple is necessary.