Warning: Disconnect power before servicing.

Noritz Water Heater Priority Light Flashing: What It Means and How to Fix It

Quick Answer

The Priority light on Noritz remote controllers (RC-7651M and similar) serves different purposes depending on the model. In multi-unit installations, the Priority designation indicates which unit responds first to a hot water demand. A steadily lit Priority light during operation is normal in this context.

The Priority light on Noritz remote controllers (RC-7651M and similar) serves different purposes depending on the model. In multi-unit installations, the Priority designation indicates which unit responds first to a hot water demand. A steadily lit Priority light during operation is normal in this context. A flashing Priority light, however, typically signals a scheduled service reminder, an active error code that should be checked on the display, or a wiring issue between the controller and the unit. Before assuming a fault, check whether your installation is single-unit or multi-unit and consult the controller's indicator legend in the owner manual.

NoritzWaterheaterSeverity: moderate80% DIY Success
Time to Fix
10–30 min
Difficulty
beginner
Parts Cost
$40 – $90
Tools Needed
Flashlight, Screwdriver (for terminal access)
Wrong code?

Not seeing PRIORITY-LIGHT on your display?

Select what your appliance is actually doing and we'll take you to the right guide.

What Does the PRIORITY-LIGHT Code Mean?

Priority light behavior depends on model and installation type. Steady on during operation is normal in multi-unit setups. Flashing usually signals a service reminder or active error code.

Most Likely Causes

Based on aggregated repair data, here is the probability breakdown for this error code:

Scheduled service reminder activated after 1 year or set interval40%
Active error code displayed alongside Priority light24%
Controller wiring or communication issue22%
Unit configured as Priority unit in multi-unit installation14%

Symptoms You May Notice

  • Priority light flashing on remote controller
  • Priority light on steady with no hot water issue
  • Priority light flashing alongside an error code
  • Priority light active after a year of use

Can you reset a Noritz waterheater to clear the PRIORITY-LIGHT code?

To clear a service reminder indicated by the Priority light, schedule and complete the annual service. After service, the technician can reset the service interval counter using the controller's service menu. A soft reset (power off 30 seconds, power on) will not clear a service reminder on most Noritz models.

Tools Required for Diagnosis

FlashlightScrewdriver (for terminal access)

Diagnostic Checklist

Follow these steps in order. We start with the easiest external fixes before opening up the machine.

1

Check the main digital display on the controller

Check the main digital display on the controller. Is there a numeric error code shown alongside the Priority light? If yes, address the error code as the primary fault using the specific code guide.

2

Check your installation type

3

Consult the service history

4

After confirming service or ruling out a fault

5

Inspect the wiring connection between the controller and the unit

Replacement Parts

If your diagnostic testing proves the component has failed, you will need a replacement. We recommend OEM parts over aftermarket for water-handling components.

Part Name
Remote Controller (RC-7651M)RC-7651M · $40–$90

Repair vs. Replace Calculator

Appliance Age (Years)7 Yrs
Labor Approach
Our Verdict
REPAIR
Estimated Cost: $65 (Parts) vs $1150 (New Machine)

Frequently Asked Questions

What does the Priority light mean on a Noritz water heater?
In a single-unit installation, the Priority light is used to indicate service reminders or alert the user to an active fault. In a multi-unit installation (two or more units linked for high-demand applications), the Priority light identifies which unit has priority status and responds first to hot water calls. Whether it is lit or flashing determines the meaning - flashing almost always indicates action needed.
How do I turn off the Priority light on my Noritz?
First confirm whether the light represents a service reminder or an error code. If it is a service reminder, complete the annual service and have the technician reset the service counter via the controller's service menu. If it is accompanying an error code, resolve the underlying fault. A simple power cycle will not clear a service reminder on most Noritz models.
Can the Priority light flash without any fault?
Yes. In multi-unit configurations, the Priority light may behave differently depending on demand and which unit is currently active. If the unit is producing hot water normally and no error code is shown on the main display, a lit or briefly flashing Priority light may simply indicate normal Priority mode operation. Confirm with your installation documentation or Noritz technical support.
My Noritz Priority light came on exactly one year after installation. Is that a service reminder?
Very likely yes. Noritz programs a 12-month service reminder into many controller models. When the interval elapses, the Priority or service light activates to prompt the annual inspection and descaling. Schedule service to reset the counter and protect the heat exchanger from scale damage.
Can I change which unit is Priority in a multi-unit Noritz setup?
Yes. Priority designation is set through the controller's system configuration menu. Consult the installation manual for the multi-unit remote controller to change the Priority assignment. Changing Priority does not affect performance - it only determines which unit receives the first call for hot water in a demand scenario.

Related Noritz Waterheater Error Codes

Models Known to Experience PRIORITY-LIGHT Errors

This repair applies to most Noritz waterheaters with this error code. Common model numbers include:

NRCP199-DV, NRCP111-DV, NR98-DV, NR66-DV, NR711

Last verified for technical accuracy on March 14, 2026