Noritz Error Code 70: Circuit Board Fault

Severity
Warning
Type
digital display
Where to look
front panel
Estimated repair cost: $100 — $350 (parts + labor)
Warning: Your Noritz water heater is experiencing a circuit board issue and has shut down to prevent damage. It's safe to troubleshoot, but call a professional if you're unsure.

How to Fix Noritz Code 70

  1. Step 1: Turn off the power to the water heater at the circuit breaker for safety
  2. Step 2: Check for any visible damage to the circuit board, such as burn marks or corrosion
  3. Step 3: If you're comfortable with electrical work, you can try replacing the circuit board with a new one. If not, call a professional

How to Reset Noritz Code 70

  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 70 mean?

The Noritz 70 error code indicates a fault with the circuit board, which controls the water heater's operation. This could be due to a short circuit, open circuit, or other electrical issue. The heater will display this error and shut down to protect itself and your home from potential damage. While it's safe to troubleshoot, it's important to know what you're doing to avoid causing further issues or injury.

Affected Models

Replacement Parts

PartOEM NumberEst. Cost
Circuit Board Noritz 4101200000

Related Codes on Same Models

CodeDescriptionSeverity
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45 Water Leak Detected Warning
51 Fan Motor Failure Warning