How to Replace a Thermal Coupler
- 1). Rotate the gas cock knob on top of the control box to the "OFF" position to cut the gas supply, then wait approximately 15 minutes for any lingering gas fumes to dissipate.
- 2). Remove the thermal coupler tube from the bottom of the control box. Three tubes attach to the bottom of the box. The burner gas tube is located in the center of the box, and is the thickest of the three tubes. The pilot gas tube is typically located to the right of the burner gas tube and is the medium-sized tube. The final tube, the thinnest of the three, is the thermal coupler tube. Twist the integral nut at the tip of the tube with a wrench in a counterclockwise direction until loose, then pull the tube out of the bottom of the control box.
- 3). Remove the water heater's inner and outer access panels to access the burner chamber. The access panels are located at the base of the water heater's tank. The outer panel is typically painted the same color as the water tank, and is held against the tank with two to four sheet metal screws. Remove the screws with a screwdriver, then pull the outer access panel away from the water heater to expose the inner access panel. Rotate the inner access panel to the side, then pull it out of the water heater.
- 4). Remove the thermal coupler from the water heater. Trace the thermal coupler's tube from the bottom of the control box to the interior of the water heater until the tip of the tube is reached. Note that the tip enters a bracket. Slide the tip out of the bracket, then pull the tube out of the water heater.
- 5). Install the new thermal coupler into the bracket within the water heater by pushing its tip into the bracket until the tip snaps into place. Tighten the integral nut at the opposite end of the thermal coupler tube into the bottom of the control box with a wrench.
- 6). Rotate the gas cock knob on top of the control box to the "PILOT" setting. Press and hold down the red button on the control box, then hold a lit match next to the tip of the pilot gas tube inside the water heater. Hold the red button down for one minute after the pilot flame lights, then release the red button and rotate the gas cock knob to the "ON" position.
- 7). Rotate the water heater's inner access panel to one side, then feed the inner panel into the water heater. Place the outer access panel against the side of the water heater, then install the panel's sheet metal screws with a screwdriver.
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