20 Most Recent Noritz 8.4 Gallon Residential Direct Vent Tankless Water Heater - N Questions & Answers

You know, either it's tankless or it's 8.4gal but it can't be both. Does that figure mean 8.4gal/minute at a certain flow rate and temperature?

Noritz 8.4... | Answered on Dec 12, 2014

A 20 error code means the high limit switch is being tripped. This is most typically caused when scale develops in the heat exchanger. I'd recommend performing a descale on the heater to resolve the problem. Make sure to follow the instructions that came with your isolator valve kit.

Noritz 8.4... | Answered on Jul 12, 2010

Electronics are very sensitive to temp, so I agree with the tech.

Noritz Water... | Answered on Nov 14, 2020

I searched for that error number 903 using https://www.google.com and saw several fraudulent sites, so beware.

There is a similar error number 90 mentioned several places, but that error requires a technician to repair it as it may be dangerous to do it yourself.

Noritz in the United States has a search feature to find a technician if you need one.


Noritz Water... | Answered on Aug 29, 2019

Code 11 is ignition failure.
Ensure that your gas is turned on.
Start by checking the vent system to ensure there is no obstruction or separation in the vent system.
Second I would recommend flushing the water heater with vinegar or Rectorseal Calci-Free. Calcium and scale build up in tankless water heaters can cause several failures that are not directly related to the specific code displayed on the heater.
If the problem persist I would look for a plumber that is familiar with tankless water heaters.

Noritz Water... | Answered on Mar 02, 2019

You should try to describe the noise and what is happening when the noise occurs. Then someone may be able to give you some diagnosis of the problem. For example, does it make a big boom sound went it lights the burners? Then you might need to clean and adjust the pilot light.

Noritz Water... | Answered on Dec 25, 2018

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

Noritz Water... | Answered on Nov 21, 2018

I need the full model number of the water heater to pull the manual on it for you.... so far only an error code 61 is shown. sometimes a 6 can look like a 5 on a digital display if it's a 6 then error code 61 is bad fan motor or printed circuit board that sends power to the fan motor.Get me the full model number, we can go from there

Noritz Water... | Answered on Nov 13, 2018

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