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Book NowYou’re washing your hands when you notice there isn’t any hot water coming from the faucet. After checking on your Noritz tankless water heater, you discover an error code but have no idea what it means. So, what next? We’ve got your back.
After 15-plus years of servicing tankless water heaters and working closely with Noritz, we’ve got a firm grasp of the most common error codes and how to treat them. In Los Angeles County, there are specific error codes that are more common than in some areas, thanks to hard water and a few other factors.
if you’re interested to learn more about Noritz besides error codes, check out our Noritz Tankless Water Heater guide.
In this article, we’ll fill you in on the most common Noritz error codes and what to do when you encounter them.
Most Common Noritz Tankless Water Heater Error Codes
Error Code 51
Starting off with error code 51, this code signals gas manifold issues or outright failure. This error code can also trigger if there’s water dripping onto the manifold. Error code 51 will likely result in gas pressure issues.
Next Steps
If you see this error code, you’ll need to call a technician out to pinpoint the issue properly. There are typically two ways these types of error code calls go.
The first possibility is that you just have a gas pressure issue. In this case, your technician will check with Noritz to get the correct gas pressure and adjust your Noritz tankless water heater accordingly via the keypad or circuit board.
On the other hand, if water is found on the manifold itself, it will require more drastic measures. If your technician finds water dripping on the manifold, they’ll have to replace it.
Error Code 11
This error code means your Noritz tankless water heater is experiencing ignition failure. There are multiple components that may play a role in this error code popping up. For instance, it could be a clog or blockage, a bad igniter or ignition rods, or the igniter box.
Next Steps
As it goes with many of these error codes, you’ll need to call out a technician to properly diagnose the issue. There are a couple of options a technician has based on the root of the problem.
Sometimes, ignition rods can become corroded, preventing the unit from igniting and producing a flame to heat water. If this ends up being the case for your tankless water heater, then your technician may choose to sand down the ignition rods.
Typically, if your technician finds a clog or blockage in the exhaust, the issue is easily resolved by removing the debris. On the other hand, if the unit just isn’t sparking, then they may need to replace the ignition box.
Error Code 12
Error code 12 is essentially the same as error code 11, meaning there’s a weak flame or none at all. The issue could be any number of things, much like with error code 11. Basically, your tankless water heater is suffering from a lack of gas or airflow due to a component issue or exhaust blockage.
Next Steps
After calling out a technician, they’ll diagnose the issue and walk you through the next steps. These next steps may include much of what was outlined in error code 12. So, your tankless water heater may be up and running in no time, or it might require a little more TLC than is ideal.
Error Code 90
While it may not be common in every region, error code 90 is one we run into frequently in Los Angeles County. This error code signals the need for maintenance and is broad in scope. If you see this error code, it could be that it received improper maintenance or is just overdue for regular maintenance.
Next Steps
This error code is a big sign that it’s time to change the way you maintain your tankless water heater. Yearly maintenance gets away from everyone, but in areas with hard water, like Los Angeles County, proper maintenance can make or break your tankless water heater’s lifespan.
The best course of action is to call a technician out for a maintenance call and get your tankless water heater back on track so it can keep up for years to come.
Error Code 16
If error code 16 builds up, it means your tankless water heater is experiencing an uptick in outlet water temperature. But this is only half of the diagnosis since this may indicate scale buildup.
Scale buildup tanks heat transfer, which means your tankless water heater will have to work that much harder to get your water up to temperature. Because of this issue, your tankless water heater will run hotter to combat the issue, resulting in error code 16.
Next Steps
Once a technician arrives at your home, they’ll likely recommend a descale right away. Technicians perform descales using a vinegar collusion that cleans out excess buildup in the tankless water heater’s system.
Additionally, your technician may recommend a water softener to prevent further issues in the future. Installing a water softener isn’t the cheapest endeavor, but proper water treatment can save you a lot of hassle in the future and prolong the life of your tankless water heater significantly.
Up to Speed on Noritz Tankless Water Heater Error Codes
We’ve run through five of the most common Noritz error codes we’ve come across in Los Angeles County. Now, you know what you might run into as a Noritz tankless water heater owner and what to do when you encounter any of these errors, so you can be confident in picking up the phone and getting the help you need.
After over 15 years of working with tankless water heaters, we can confidently tell you that you’ll likely run into an error code or two within your tankless water heater’s lifespan. It’s important to know what they mean, but equally as important is knowing who to call.
It’s always wise to call a professional when an error code pops up on your tankless water heater. While it doesn’t have to be us, just be sure you call a trustworthy technician to solve your problem. That said, if you need a hand, visit our tankless water heater service page or click one of the buttons below to schedule a consultation.
If you’re still new to tankless water heaters, download our Noritz Tankless Water Heater guide to get up to speed on your investment. Similarly, if you’re not sure what you need to do to prevent error codes, you can start by familiarizing yourself with the types of maintenance a tankless water heater needs.
