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How to Care for and Troubleshoot Your Noritz Tankless Water Heater

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tankless water heater troubleshooting

Noritz tankless water heaters present you with error codes when something is wrong, and knowing how to understand these error codes and troubleshoot them appropriately is truly vital. That’s what we’re going to cover for you today. We know how frustrating it can be when you’re faced with what seems like a random code that you’ve never seen before. But we’re about to clear things up for you.

We’ll first discuss how to take care of your Noritz tankless water heater and then move onto the common problems and the error codes attached to them. That way, you’ll know what the problem is and what to do about it next time your water heater displays an error code. Read on now to find out more.

How to Care for Your Noritz Tankless Water Heater

One thing you can and should do regularly to maintain your Noritz tankless water heater in the right way is to purge the port valves. You do this by attaching hose lines and opening the relevant purge port valves. As long as you prepare properly and have a safe discharge location, this should be an easy process and it’ll remove waste from the heater system.

You can also use undiluted white vinegar to clean out the water heater now that you’ve purged its lines. There’s a range of draining and flushing procedures recommended by the manufacturer so be sure to follow these when cleaning out the water heater. Whatever you do, don’t use harsh chemicals during the cleaning process because these will only cause damage.

When all that’s done, you’ll want to turn the water on again. This is something that you should do slowly in order to remove any trapped air from the system. Do it by finding the faucet furthest away from the heater and turning it on slowly because this will remove the air safely.

Noritz Tankless Water Heater Troubleshooting Guide

When you see an error code, it means there’s something wrong with your Noritz tankless water heater. Most of these problems can be fixed pretty easily with a basic set of tools, even if you’re no expert. Find out about some of the most common error codes and how to troubleshoot them below.

Error Code 05

This is an automatic service reminder telling you that your system is due to a service. When you see this, call a licensed technician and book a service.

Error Code 10

If the combustion continues or the power drops even after the unit has been turned off, you’ll see this error code. Look for foreign objects and materials like oil and grease on the burner that might still be burning.

Error Code 11

Error Code 11 signals a problem with the ignition. When there’s an ignition failure in your water heater, you should check the gas pressure and see if there’s anything obstructing the air supply. Any such obstructions should be removed.

Error Code 12

When the water isn’t being heated properly, it’s often because of a weak flame. Check the airflow is correct and make sure the flame sensor isn’t being covered by any debris. Cleaning it might fix the problem too.

Error Code 14

This error code means the thermal flame has failed for some reason. It might be necessary for you to replace the thermal flame. Flushing the heat exchanger and checking the water quality is important because this can cause it to clog up.

Error Code 16

This error code is telling you that the water temperature is too high. This is usually caused by scale buildup or hard water, so descaling the system is a good idea. The maintenance process described above can be used.

Error Code 20

This error code shows when the high limit switch has been activated. Checking the switch and replacing it if necessary is one thing you can do. If that’s not necessary, descaling the water heater might be the answer.

Error Code 29

When the water level in the neutralizer isn’t draining correctly, you’ll see Error Code 29. To overcome the problem, you’ll need to ensure the condensate drain line is correctly routed and no obstructions are causing problems.

Error Code 59

This error code means that there’s low gas BTU input and that combustion problem are being caused as a result. Ensure air is flowing to the combustion chamber and set the correct gas pressure to address the problem. Cleaning the fan and burner chamber might help too.

Be sure to follow the advice outlined above next time you have a problem with your Noritz tankless water heater. Just find the error code that’s being displayed and take the actions we’ve described here.

Need help with your tankless water heater in Southern California? Contact us today!

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