Applies to: SENSEI SENSEI RX/CX Non-SENSEI
What you can safely check
- Look at the vent caps outside: clear snow, leaves, nests or anything blocking them.
- Check the condensate drain line (condensing models) isn’t clogged, kinked or frozen.
- Clean the inlet air filter under the front cover, if your model has one, with the power off.
What a technician will look at
Everything past the checks above involves gas pressure, live electrical parts or opening the sealed cabinet. That work is for a licensed gas or plumbing professional. For code 10, Rinnai’s service steps cover:
- full vent system and vent materials
- combustion fan
- heat exchanger
Smell gas? Don’t touch switches or try to reset the heater. Leave the building and call your gas supplier or 911 from outside.
Source: Rinnai, Troubleshooting Tankless Water Heater Diagnostic Codes (document 100000652), page 12. The code name is Rinnai’s; the explanation is ours. Codes differ between series – check the model on your heater’s rating plate. This site is independent and not affiliated with Rinnai.