Noritz Error Code 71: Gas Valve Drive Circuit Abnormality

Severity
Warning
Type
digital display
Where to look
front panel
Estimated repair cost: $200 — $500 (parts + labor)
Warning: Your Noritz water heater is experiencing a gas valve drive circuit issue and has locked out to prevent safety hazards. Call a professional for repair.

How to Fix Noritz Code 71

  1. Step 1: Turn off the power to your water heater at the circuit breaker.
  2. Step 2: Call a licensed HVAC technician to diagnose and repair the issue.
  3. Step 3: Do not attempt to open the water heater or tamper with any internal components.

How to Reset Noritz Code 71

  1. Turn off the unit using the power button on the front panel.
  2. Turn off the gas supply valve.
  3. Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
  4. Restore power at the breaker, then open the gas valve.
  5. Turn the unit back on. If the error returns, the underlying issue needs repair.

What does 71 mean?

Error code 71 on your Noritz water heater indicates a problem with the gas valve drive circuit. This circuit controls the gas valve that supplies fuel to the burner. When an abnormality is detected, the unit locks out to ensure safety. Common causes include electrical issues, such as a short circuit or open wire, or problems with the gas valve itself. Don't attempt to fix this issue yourself; always call a licensed technician.

Affected Models

Replacement Parts

PartOEM NumberEst. Cost
Gas Valve Assembly
Control Board

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