Price Match Guarantee
In-stock parts ship the same day
365-Day Return Policy
Price Match GuaranteeGET PRO PRICING
Video & Articles: Appliance & Equipment RepairWater Heater Won't Light? Igniter & Flame Sensor #9005958005
Water Heater Won't Light? Igniter & Flame Sensor #9005958005
Skill Level
Total Parts Cost
$152.51Estimated Savings
$112.5004:56
- Description
This video provides step-by-step instructions for replacing the igniter and flame sensor on AO Smith gas water heaters. The most common reason for replacing the igniter and flame sensor is when the water heater does not light or does not heat.
All of the information in this igniter and flame sensor replacement video is applicable to the following brands: AO Smith
Tools used: 3/8” socket, adjustable wrench, needle-nose pliers, Phillips head screwdriver, adhesive
All of the information in this igniter and flame sensor replacement video is applicable to the following brands: AO Smith
Tools used: 3/8” socket, adjustable wrench, needle-nose pliers, Phillips head screwdriver, adhesive
Step By Step Instructions
1
Before you replace the igniter and flame sensor in your water heater unplug the power cord
2
Shut off the gas supply.
3
Next, remove the burner access cover.
4
Use a 3/8th inch socket to help unthread the mounting nuts securing the burner cover.
5
Use a 3/4th inch wrench to unthread the nut securing the burner tube to the control valve.
6
Disconnect the igniter and sensor wire harness from the valve.
7
Detach the vapor sensor and bracket from the tank base and pull the burner assembly free.
8
Remove the twist retainer to release the wires.
9
Disconnect the wires from the vapor sensor.
10
Detach the grommet and push the wires through the burner cover.
11
Use a phillips-head screwdriver to remove the mounting screw securing the igniter and flame sensor and pull the old elements free.
12
Push the burner tube gasket through the cover to fully release the burner tube.
13
Before you install the new igniter and flame sensor peel off the old insulation from the burner cover.
14
Apply some high temperature adhesive then align the new insulation on the inside of the cover.
15
Once secured, insert the burner tube and gasket through the large hole in the cover and push the gasket into place.
16
Next, align the new igniter and flame sensor on the burner tube bracket and replace the mounting screw to secure.
17
Feed the wires through the small hole in the cover and push the grommet into place.
18
Connect the wires to the vapor sensor.
19
Make sure to align the burner tube on the support bracket as you reinstall the burner assembly in the tank.
20
Thread and tighten the nuts to secure.
21
Snap the vapor sensor bracket into place on the tank base.
22
Connect the igniter and sensor wire harness to the control valve.
23
Reattach the burner tube to the valve by threading and tightening the nut.
24
Use the twist retainer to secure the wires.
25
Replace the access cover.
26
With the repair completed turn the gas supply back on plug the power cord back in and your water heater should be ready for use.
Description
This video provides step-by-step instructions for replacing the igniter and flame sensor on AO Smith gas water heaters. The most common reason for replacing the igniter and flame sensor is when the water heater does not light or does not heat.
All of the information in this igniter and flame sensor replacement video is applicable to the following brands: AO Smith
Tools used: 3/8” socket, adjustable wrench, needle-nose pliers, Phillips head screwdriver, adhesive
All of the information in this igniter and flame sensor replacement video is applicable to the following brands: AO Smith
Tools used: 3/8” socket, adjustable wrench, needle-nose pliers, Phillips head screwdriver, adhesive
Step-By-Step Instructions
1
Before you replace the igniter and flame sensor in your water heater unplug the power cord
2
Shut off the gas supply.
3
Next, remove the burner access cover.
4
Use a 3/8th inch socket to help unthread the mounting nuts securing the burner cover.
5
Use a 3/4th inch wrench to unthread the nut securing the burner tube to the control valve.
6
Disconnect the igniter and sensor wire harness from the valve.
7
Detach the vapor sensor and bracket from the tank base and pull the burner assembly free.
8
Remove the twist retainer to release the wires.
9
Disconnect the wires from the vapor sensor.
10
Detach the grommet and push the wires through the burner cover.
11
Use a phillips-head screwdriver to remove the mounting screw securing the igniter and flame sensor and pull the old elements free.
12
Push the burner tube gasket through the cover to fully release the burner tube.
13
Before you install the new igniter and flame sensor peel off the old insulation from the burner cover.
14
Apply some high temperature adhesive then align the new insulation on the inside of the cover.
15
Once secured, insert the burner tube and gasket through the large hole in the cover and push the gasket into place.
16
Next, align the new igniter and flame sensor on the burner tube bracket and replace the mounting screw to secure.
17
Feed the wires through the small hole in the cover and push the grommet into place.
18
Connect the wires to the vapor sensor.
19
Make sure to align the burner tube on the support bracket as you reinstall the burner assembly in the tank.
20
Thread and tighten the nuts to secure.
21
Snap the vapor sensor bracket into place on the tank base.
22
Connect the igniter and sensor wire harness to the control valve.
23
Reattach the burner tube to the valve by threading and tightening the nut.
24
Use the twist retainer to secure the wires.
25
Replace the access cover.
26
With the repair completed turn the gas supply back on plug the power cord back in and your water heater should be ready for use.
Applicable Product Model
Parts Needed
Igniter
$152.51
Total$0.00
Related Articles & Videos
Our Story
Family-owned and operated since 1912, Burke America Parts Group is the longest-running genuine appliance, HVAC, and outdoor power equipment parts solution in North America. At Repair Clinic, we're proud to be an international brand trusted by the pros as well as the DIY community.
About Repair Clinic
© 2026 RepairClinic.com