Ask us anything

How to replace a hot surface gas igniter A.O. Smith water tank?

Replacing a hot surface gas igniter in an A.O. Smith water tank is a task that can restore your water heater's ignition system's functionality, ensuring it can safely and efficiently heat water. The igniter is a critical component responsible for lighting the gas burner. If it's not working correctly, your water heater won't function as intended. Here's a step-by-step guide on how to replace a hot surface gas igniter in an A.O. Smith water tank:

1. Safety First:
Before you begin any work on your water heater, ensure your safety by turning off the gas supply to the unit. Locate the gas valve on the gas line leading to the water heater and turn it off. Additionally, shut off the power to the water heater at the circuit breaker or disconnect the power source if it's an electric model.
2. Gather the necessary tools and materials:
You will need a replacement hot surface igniter suitable for your A.O. Smith water tank model, a wrench or socket set, a screwdriver, and possibly pliers.
3. Access the burner assembly:
To access the hot surface igniter, you'll typically need to remove the burner assembly cover or panel on the water heater. Use a wrench or socket set to loosen and remove any screws or bolts securing the cover. Keep all removed parts organized for easy reassembly.
4. Locate and remove the old igniter:
The hot surface igniter is typically positioned near the gas burner, attached to a bracket. Carefully disconnect any wires or connectors leading to the igniter. You may need to use pliers to gently pull the connectors apart. Note the wiring connections or take a photo for reference when reconnecting the new igniter.
5. Remove the old igniter from its bracket:
The igniter is usually held in place by one or more screws or bolts. Use a screwdriver or a wrench to remove these fasteners and release the old igniter from its bracket. Take care not to damage the bracket or surrounding components.
6. Install the new igniter:
Position the new hot surface igniter in the same location as the old one, using the bracket. Secure it in place by tightening the screws or bolts you removed in the previous step. Ensure the igniter is properly aligned and securely attached.
7. Reconnect the wiring:
Reconnect the wires or connectors to the new igniter in the same configuration as they were on the old one. Refer to your notes or the reference photo if necessary. Ensure the connections are tight and secure.
8. Reassemble the burner assembly:
Carefully put the burner assembly cover or panel back in place and secure it with the screws or bolts you removed earlier. Tighten them securely to prevent any air or gas leaks.
9. Turn on the gas supply:
Turn the gas valve on the gas line leading to the water heater back on. Be cautious and ensure there are no gas leaks; you can use a gas leak detector solution or soapy water to check for leaks around connections.
10. Restore power:
If you had to disconnect the power supply, reconnect it and restore power to the water heater at the circuit breaker or power source.
11. Test the water heater:
Turn on the hot water tap at a faucet in your home to activate the water heater. Observe the ignition process to ensure the hot surface igniter is working correctly. It should glow red-hot, and the burner should ignite. If you encounter any issues, turn off the water heater and double-check your connections and installation.
12. Monitor for proper operation:
After successfully replacing the hot surface igniter, keep an eye on your water heater's performance to ensure it continues to operate without problems. If you notice any irregularities or issues, consult a professional technician for further inspection and assistance.

By following these steps and taking safety precautions, you can effectively replace the hot surface gas igniter in your A.O. Smith water heater, restoring its functionality and ensuring you have a reliable source of hot water. If you are uncertain about any part of the process or encounter any difficulties, consider seeking the assistance of a qualified plumber or technician.
Connect to virtual expert

Our virtual experts can diagnose your issue and resolve simple problems.