Rheem Tankless Water Heater Error Code 11: Meaning and Fix
Applies to: Rheem Eagle series tankless water heaters, indoor and outdoor (Use and Care manual AP22009, Service Error Code Chart); other Rheem tankless lines such as RTGH may use different codes.
Reading the tankless water heater display
A tankless water heater shows its fault as a number or letter code on the unit display or on the wired remote controller, and some models keep a short history of past codes. Write the code down exactly as shown before you reset the unit, and check the rating plate for the model number, because the same number can mean different things between series.
This page lists the fault codes this brand documents, with likely causes and a short repair path. Check the model label on your unit before using any chart.
What causes 11
- Gas shut-off valve partly closed
- Handle moved by accident
- Valve closed after service
How to fix it
If you smell gas, leave the building and call your gas utility from outside; do not touch switches or the unit. Switch the water heater off and let it cool before you touch any internal part, and call a licensed plumber or water heater technician if you are not sure.
The code meaning comes from the manufacturer document listed under Sources. The causes and steps below are general troubleshooting guidance, not the manufacturer's service procedure.
- Switch the water heater off and let it cool before you touch anything inside it. If you smell gas, leave the building and call your gas utility from outside.
- Check the gas shut-off valve at the water heater.
- Open it completely so the handle lines up with the pipe.
- Run a hot tap to see whether the code clears.
- If the code returns after these checks, call a licensed plumber or water heater technician and give them the code and the model number from the rating plate.
Questions
What does Rheem tankless error code 11 mean?
Code 11 on a Rheem Eagle tankless water heater means the gas shut-off valve is not fully opened. Rheem's solution is to check the shut-off valve and open it completely.
Can I reset the water heater myself?
Turning the unit off and back on, or unplugging it for about 30 seconds, clears some codes. If the same code comes back, the fault is still there and the unit will shut down again. Do not bypass a safety device to keep it running.
When should I call a technician?
Call a licensed plumber or water heater technician for anything involving gas, venting, the heat exchanger, a thermal fuse or the circuit board, or when the code keeps returning after the simple checks.
Other brands with code 11
The same code can mean something different on another maker's appliance. Check the brand before you act.
Other Rheem tankless water heater codes
Sources
Part numbers are OEM references; confirm fit by your model number before ordering. Meanings compiled from manufacturer and parts-retailer documentation; see sources below. Unplug the appliance before opening it.