How to replace lighting sensor on A.O. Smith water heater?

A.O. Smith water heaters often come equipped with lighting sensors to ensure safe and efficient operation. If you're experiencing issues with your water heater, and you suspect the lighting sensor is faulty, you may need to replace it. Here's a step-by-step guide on how to replace a lighting sensor on an A.O. Smith water heater:

Tools and Materials You'll Need:
* Replacement lighting sensor (make sure it is compatible with your A.O. Smith water heater model).
* Screwdriver.
* Adjustable wrench or pliers.
* Safety goggles and gloves.


Step 1: Safety Precautions
Safety should be your top priority when working with gas appliances. Before you begin, turn off the gas supply to the water heater. Locate the gas valve, usually located on the gas pipe leading to the heater, and turn it to the "off" position. Additionally, make sure the water heater has cooled down to prevent burns during the replacement process.
Step 2: Identify the Lighting Sensor
The lighting sensor is typically located near the pilot light assembly inside the water heater. It may be connected to the gas control valve or mounted separately within the combustion chamber.
Step 3: Disconnect the Electrical Wires (if applicable)
Some lighting sensors are electrically connected to the gas control valve. If your lighting sensor has electrical wires connected to it, carefully disconnect these wires. Use a screwdriver or pliers to loosen the terminal screws and remove the wires. Take note of the wire connections for reinstallation.
Step 4: Remove the Old Lighting Sensor
Depending on your water heater model, you may need to remove the pilot burner assembly or the combustion chamber access panel to access the lighting sensor. Refer to your water heater's user manual for specific instructions on how to access the sensor.
Once you have access to the lighting sensor, carefully remove it. If it is held in place with screws, use a screwdriver to loosen and remove them. If it is clipped or mounted with brackets, gently unclip or disengage it from its holder.
Step 5: Install the New Lighting Sensor
Take your replacement lighting sensor and position it in the same location as the old one. Ensure it is properly aligned and seated. Secure it in place using the screws, brackets, or clips that were removed during the removal process.
Step 6: Reconnect Electrical Wires (if applicable)
If your lighting sensor had electrical wires, reconnect them to the appropriate terminals on the gas control valve. Tighten the terminal screws to ensure a secure connection.
Step 7: Reassemble the Water Heater
If you had to disassemble any components to access the lighting sensor, reassemble them in the reverse order of disassembly. This may include reattaching the pilot burner assembly, combustion chamber access panel, or other parts that were removed.
Step 8: Check for Proper Installation
Ensure that the new lighting sensor is securely in place and properly aligned with the pilot light. Verify that any electrical connections (if applicable) are tight and secure.
Step 9: Turn On the Gas Supply
Turn the gas supply back on by rotating the gas valve to the "on" position. If your water heater has a pilot light, follow the manufacturer's instructions for relighting the pilot.
Step 10: Test the Water Heater
After relighting the pilot, give the water heater some time to heat the water. Test the hot water supply at a faucet to ensure it's working correctly. Monitor the water heater for any signs of issues or malfunctions.

By following these steps, you can replace the lighting sensor on your A.O. Smith water heater. If you encounter difficulties or are uncomfortable with any part of the process, it is advisable to seek the assistance of a qualified technician or plumber to ensure your water heater operates safely and efficiently. Safety is paramount when working with gas appliances, so exercise caution and adhere to manufacturer guidelines and local regulations at all times.