Noritz error code 71

Remove the bird's nest in the flue.

The 10, 59, 90 and 99 error codes indicate that a Noritz heater has experienced a combustion abnormality. In most cases, it is the result of an obstruction in the heater's flue. Examine the flue to see if it is blocked by debris and clean if necessary.

How To Resolve The Seven Most Common Noritz Tankless ...

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Nov 16, 2015 - This error code involves a breakdown in communication between two tankless water heaters using the Quick Connect Cord. It can occur when more ...

Troubleshooting Noritz Tankless Water Heaters and Error Codes

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Error code 90 and 99 ... Action: Check for the obstructed venting, improper gas burning (flame shape and color change). Ensure the water heater gets the ...

Error Codes for a Noritz Water Heater - Waterheatertimer.org

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Here is a link to all the Noritz error codes. There is NO Code 67. https://inspectapedia.com/heat/Noritz-NCC199-Error-Codes.pdf

The Noritz Manual shows fixed for the following error codes:
11
21
90
99
For all other codes this is the recommendation:
Contact our sales agent if:
• Any other error code appears.

F76 is usually a communication error between the remote and the heater. you may have just unplugged something inside the unit while it had power (don't do that). Just unplug the unit from the wall (or flip the breaker) and wait 10 sec and plug it back in again and the problem should fix itself. Otherwise there my be a loose wire going to your remote. In which case, try unplugging the remote and unit for 10 sec and plug the unit (only) back in with the remote disconnected. run your hot water and see if it works. if so it could be a problem with the remote or its wiring.

EC 71 usually means you are using a battery backup that doesn't produce a pure sine wave. OR you recently had a power outage and it shorted the circuit board. if you have a battery backup try unplugging that and see if it works okay. If not, just call Noritz for a replacement c/b.

F76 is a communication error. It usually occurs if you connect or disconnect a quick connect cable or remote control when the tankless heater is connected to electricity. (If you have a quick connect system, make sure you only have 1 remote and 1 quick connect cable.) To get rid of the code, try disconnecting electricity for 20 seconds, reconnecting electricity, and turning the remote on. If the code returns, you may need to replace your quick connect cable, remote cable, or even remote control

a 16 error code is typically caused by scale formation. I'd recommend performing a descale on the heater.

Here are a couple things to look for:

1) flashing burner light - a flashing burner light indicates the unit is getting an error code
common error codes:
A. continuous flashing - ignition failure or abnormal combustion; look for visible water in the machine indicating a leak, check gas pressure, debris or buildup on flame rod/igniter plug, or clean unit with compressed air
B. 3 flashes - error 16, abnormal outlet water temperature; typically this code indicates you'll need to descale you unit
C. 4 or 5 flashes - exotic error codes; you should contact Noritz technical support to deal with these codes

2. If there is no flashing code, try increasing the hot water flow. In the summer time you typically use less hot water; this can result in intermittent operation of your tankless heater. Increase water flow by either: A. cleaning your showerhead and removing scale deposits B. widening your flow restrictor C. Remove your flow restrictor in the showerhead

3.If none of these resolves your problem, you probably have debris in your flow sensor. Contact Noritz technical support for a walkthrough on removing debris from a flow sensor.

You are actually getting a 90 error code. This error code occurs if the unit is dirty and overheating. I'd recommend contacting a servicer to clean your heater with compressed air. They'll need to remove the fan motor and manifold plate to fully clean the burner chamber and heat exchanger.