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Error codes can alarm and frustrate. Use this guide to identify the problem — and then contact a professional plumber for expert assistance.

Noritz tankless water heaters are engineered to operate at maximum efficiency 24/7/365 for home and business owners. But occasional error codes can appear on the units. These codes can alert homeowners to problems that go unnoticed until complete unit failure. On the other hand, the meaning and import of individual codes may not be immediately available to them.

To ensure that water heater owners know what to expect when they receive an error code, we asked Desiree Lovelady, Noritz service technician lead, to review the five most common error codes. Some codes have relatively simple resolutions; nonetheless, but Noritz strongly recommends that you contact a licensed plumbing and heating contractor to deal with them.

Error Code 90

This code indicates a combustion abnormality caused by an improper mixture of air and fuel. It can occur from an insufficient gas supply, blockage in a fuel vent, or debris in the fan motor.

This issue requires the skills of a licensed plumbing and/or heating contractor to check gas pressures, venting length and dip switches for the cause of the issue. When you see this code, contact a contractor right away!

Error Code 73

This error means that there are improper circuit-board settings for a water heater. This can happen if a jumper connection or a dip switch is changed while power is supplied to the heater. An improperly programmed circuit board could also create the issue.

When this happens, unplug the heater for 30 seconds and then plug it back in. If this does not resolve the issue, please contact a licensed contractor.

Error Code 29

This error code indicates an issue with condensate drainage. Condensing water heaters use a drain line equipped with a neutralizer to remove the condensate. If this line is blocked or proper drain piping is not used, the burner could flood.

The typical fix for this error code is to clean out the container and drain line of any debris or blockages. You should also make sure there are no flat runs or 90-degree elbows in the drain line.

Error Code 11

This code signals an ignition failure, without which no water will be heated. Possible causes: an insufficient gas supply, problems with air flow, or debris on the ignition plug.

When seeing this error code, first make sure that your gas is on. If it is, check gas pressures and test the spark. Both tasks call for a licensed contractor.

Error Code 16

This error code can pop up when there is considerable scale buildup in your water heater. Scale decreases heat-transfer efficiency and will make the heater burn hotter to compensate.

Annual maintenance, using a descaling procedure or water softener, can prevent this code. If you need further assistance, once again, contact a licensed contractor.

To learn more about the products offered by Noritz, click here: https://www.noritz.com/products/

For help with finding a licensed contractor to fix these various error codes, please use the Noritz Find a Service Rep tool.