Error Codes · Rheem

Rheem Tankless Water Heater Error Codes

Text us with your make, model, and error code—Blue Conservation will help you troubleshoot fast.

Blue Conservation’s trained Rheem specialists can troubleshoot error codes and restore your tankless water heater. Text us with your code, model, and symptoms for the fastest response.

Rheem Units Covered

Error codes below apply to the models listed. Newer or discontinued models may not be shown.

Models Covered

RTGH-S/SR, Prestige RTGH, TK-808NR-REV

Blue Conservation recommends contacting a licensed and trained service technician for troubleshooting and repairs. The information below is presented for informational purposes only, not as guidance or instruction. Customers who remove the cover from any equipment do so at their own risk and responsibility. For service and assistance, please contact Blue Conservation at 484-469-0718 during regular business hours. For members of our Blue Club service plan, feel free to call or text service requests at any time and we will look to respond as soon as possible.

Rheem Tankless Water Heater Error Codes

Error codes are for informational purposes only. Call or text Blue Conservation at 484-469-0718 for professional service.
ManufacturerError CodeDescription
RheemError Code 1LWater heater has a buildup of lime depositsCall or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 05Air intake or vent exhaust opening may be blockedRemove any blockage. (Air intake requires 12 inches [30 cm] of clearance.) The vent pipes on the vent termination may not be connected properly. Call or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 11The gas shutoff valve is not fully openedCheck the shutoff valve and open completely.
RheemError Code 12Gas service has been interruptedContact your gas utility company. LP gas is running low (LP models only)Refill or replace your LP gas container.
RheemError Code 13If this code is still displayed after taking the numbered steps above, call or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 14Water heater is overheatingCall or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 15The heat exchanger is too hot Call or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 29Neutralizer is cloggedCall or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 31Faulty inlet thermistorCall or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 33Faulty outlet thermistorCall or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 61or 99Faulty blower motorCall or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 65Faulty water flow solenoidCall or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 92The neutralizer needs to be replaced soonThe unit can be used for a while, but call or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code 93The neutralizer must be replacedThe unit cannot be used until the neutralizer is replaced. Call or text Blue Conservation’s trained Rheem specialists at 484-469-0718.
RheemError Code P1Not enough water flow to operate the unitIncrease the water flow from the fixtures.
RheemError Code 88Reminder to flush the heat exchanger and/or replace the water treatment filter.Call or text Blue Conservation’s trained Rheem specialists at 484-469-0718.

Other Manufacturer Error Codes

Browse error codes for other major tankless brands.
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Emergency Response

Blue Conservation often troubleshoots error codes over the phone, and we do our best to respond as quickly as possible to emergency requests. Response times will vary depending on the nature of the malfunction, time of day (or night), and personnel availability, but we take pride in our customer service and satisfaction.

BLUE CLUB MEMBERS ALWAYS GET PRIORITY SERVICE! Let us know if you are a Blue Club member—members receive priority and expedited services. Learn about Blue Club →

If you are experiencing a boiler, combi, or tankless water heater emergency, text us right away at 484-469-0718.

Please Include the Following Information

Text Us With the Correct Information

Have your Rheem make, model, and error code ready. Text 484-469-0718 or request service online.

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