Rheem does not give a one-line definition for code 11 in the manual we reviewed; it groups it with code 12 under shared causes. Newer IKONIC models use different codes, so check your model.
Safety first
Rheem's manual says not to attempt repair of electrical wiring, gas piping, burners, vent connectors or other safety devices. If you smell gas, leave and call SDG&E or 911 from outside.
Causes Rheem lists
- The air intake or vent exhaust opening may be blocked.
- Vent pipes not connected properly.
- The gas shutoff valve is not fully open.
- Gas service has been interrupted.
- LP gas is running low.
What you can safely do
- Clear anything blocking the air intake or exhaust. Rheem calls for 12 inches of clearance at the air intake.
- Open the gas shutoff valve fully; call the gas utility if service is interrupted, or refill the LP tank.
- Restart: turn off the hot water taps, power off with the remote, wait about 5 minutes and restart; or unplug the unit for about 30 seconds.
When to call a plumber
If the code persists, or the venting looks disconnected, Rheem says to contact a dealer or qualified service technician.
General information, not professional or legal advice; follow your manufacturer's manual, and your installer and local permit office have the final word. Sources:Rheem Noncondensing Tankless Use & Care Manual (AP18000-2). SD Water Heaters is not affiliated with any manufacturer; brand names are used only to identify products, and codes can differ by model, so confirm in your own manual.
Water Heater Repair in San Diego →