Open following link for useful troubleshooting information:
http://waterheatertimer.org/Troubleshoot-Rheem-Tankless-water-heater.htmlError code 11 is 'No ignition'
http://waterheatertimer.org/pdf/Paloma-Tankless-Error-Codes.pdfEnsure you have gas to the appliance.
Ensure gas type and pressure are correct.
Bleed all air from gas lines.
Ensure gas line, meter, and regulator are sized properly.
Ensure appliance is properly grounded.
Check gas solenoid valves for open or short circuits.
Ensure igniter is operational.
Check igniter wiring harness for damage.
Error code 12 is 'Flame Failure'Ensure you have gas to the appliance.
Ensure gas type and pressure are correct.
Bleed all air from gas lines.
Ensure flame rod wire is connected.
Check flame rod for carbon build-up.
Ensure gas line, meter, and regulator are sized properly.
Ensure appliance is properly grounded.
Check gas solenoid valves for open or short circuits.
Check power supply for loose connections.
Check power supply for proper voltage and voltage drops.
Disconnect remote control.
Disconnect and re-connect all wiring harnesses on unit and PC board.
Ensure proper venting material was installed.
Ensure condensation collar was installed properly.
Ensure maximum vertical vent length does not exceed allowable limits.
Ensure maximimum horizontal vent length does not exceed allowable limits.
Range of causes are part failure, gas pressure loss, air in gas line, improper installation of gas line or vent, 120V power to unit is disrupted or unit not grounded, circuit problems, venting problems, remote control, wiring to PC board, board failure, carbon build-up on flame rod, short circuits on gas valve solenoids.
The fact that you have error code tends to eliminate your plumbing as culprit, the error code does not mention air supply, otherwise it looks like every possible cause is on the table.
Add a comment with your experience so other with same-similar problem can benefit.
Also take advantage of fixya expert assistance live.
For a price, expert works with you while you work on water heater or any do-it-yourself project.
Fixya is always less expensive than a service call.
×