73 🟡 Repair Required

Noritz Error Code 73: Circuit Board Setting Error

⚠️ Your Noritz water heater is experiencing a circuit board setting error, which has caused it to shut down. It's safe to troubleshoot, but don't attempt any repairs yourself.

How to Fix Noritz Code 73

  1. Step 1: Turn off the power to your Noritz water heater at the circuit breaker.
  2. Step 2: Wait for 30 seconds, then turn the power back on. The unit should reset and try to boot up.
  3. Step 3: If the error persists, or you hear unusual noises, call a professional HVAC technician.
Type: digital display Display: front panel

What Does Noritz Error Code 73 Mean?

The Noritz 73 error code indicates a problem with the circuit board's settings. This could be due to a software glitch, a power surge, or a faulty component. The unit has entered a safe mode and shut down to prevent further damage. Before you call a professional, let's try a simple reset.

Common Causes of Noritz Code 73

  • A power surge or fluctuation
  • Software glitch due to a recent update or power outage
  • Faulty component on the circuit board

Applicable Noritz Models

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Replacement Parts for Noritz Tankless Water Heater Code 73

Circuit Board OEM: NR-CB-001