How to Troubleshoot a Hot Water Heater With a Pilotless Ignition

Newer hot water heaters that operate with gas also use a pilotless ignition system with a hot-surface igniter.
The igniter in a hot water tank is mounted on the inside near the bottom.The igniter in a hot water tank is mounted on the inside near the bottom.
The blade on the igniter glows orange, reaching a preset temperature that causes the valve in the gas line to open. This lights the burner assembly for heating water in the tank. The igniter may be prone to wear out faster than other parts in the tank since it is exposed to frequent high heat. Troubleshooting the part takes only a few minutes with an ohmmeter.

Step 1

Turn off the circuit breaker for the hot water tank. Wait at least 30 minutes for the internal electrical components to cool down. The water in the insulated tank will remain hot, but you will be able to test the igniter system.

Step 2

Take out the screws in the curved metal access panel near the bottom of the tank then remove the panel. The igniter is inside the tank compartment at the bottom with the flat end pointed toward the gas valve.

Step 3

Disconnect the back of the igniter from the socket where the two igniter wires are attached to a plastic plug. Do not touch the front tip of the part.

Step 4

Touch the ohmmeter probes to the two electrical contacts in the plug wired to the igniter. If the display remains at zero or scrolls to the infinity range, the igniter is defective and must be replaced.

Things You Will Need

  • Screwdriver set
  • Ohmmeter

About the Author

James Clark began his career in 1985. He has written about electronics, appliance repair and outdoor topics for a variety of publications and websites. He has more than four years of experience in appliance and electrical repairs. Clark holds a bachelor's degree in political science.