Rinnai · Tankless water heater

22 Gas valve adjustment fault

Medium severity SENSEI RX/CX

What the control is telling you

Fault with gas valve adjustment, typically linked to the front reed switch position or incorrect gas valve parameters.

Applies to: SENSEI RX/CX Series

Likely causes

Reed switch on front of gas valve not positioned correctly
Incorrect gas valve parameters

Test and repair steps

Confirm the reed switch on the front of the gas valve is seated in its correct location.
Check all gas valve parameters; if any are wrong, re-enter them per the Gas Valve Replacement Instructions (100000855).

Settings for these units

RX supply connection sizes · SENSEI RX/CX
RX water quality limits · SENSEI RX/CX
RX water treatment and flushing by hardness · SENSEI RX/CX
RX clearances to combustibles · SENSEI RX/CX
RX temperature settings available · SENSEI RX/CX

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Source: Rinnai Troubleshooting TWH Diagnostic Codes (100000652), p.33. Summarized in our own words; check the original manual for your model.

Homeowner looking at this code? See what it means for you and when to call a technician.

For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.