Icon
Reliable Heating and Cooling Solutions – Quality Service, Fair Prices, Guaranteed Satisfaction!

Rinnai Error Code 30: Flammable vapor sensor activated or faulty (Tankless)

Updated · by Aurora Star Tech Inc.

Rinnai error code 30 on a tankless water heater means: Flammable vapor sensor activated or faulty. It is also called Rinnai diagnostic code 30.

Critical severityTankless Water HeaterRH180 hybrid

Homeowner? What Rinnai code 30 means for you

Stop and call Your tankless water heater is reporting: Flammable vapor sensor activated or faulty. This code is a safety shutdown. Turn the tankless water heater off and call a licensed technician. Do not keep resetting it. If you smell gas, leave the house and call your gas utility or 911 from outside.

Safe things you can check yourself

  • Check that gas reaches the house: other gas appliances work, or the propane tank is not empty.
  • Make sure the heater is plugged in and its breaker is on. In winter, keep the power on: it protects the unit from freezing.

Call (647) 657-2977Book a service call

Licensed technicians serving Vaughan, Toronto and the GTA.

What does Rinnai error code 30 mean?

The flammable vapor sensor has tripped or failed; flammable vapors may be present near the water heater.

Applies to: RH180 (Hybrid Tank-Tankless Non-SENSEI Series)

Common causes of Rinnai code 30

  • Flammable vapors present in the installation space
  • Loose, damaged or broken sensor wiring or connectors
  • Flammable vapor sensor mis-mounted or damaged

A technician checks these and 2 other possible causes on site before replacing any part.

Safety: Gas, electrical and refrigerant work must be done by a licensed technician. Turn off power and gas before servicing, never bypass a safety control, and always follow the manufacturer's manual for your exact model.

Rinnai models that use code 30

RH180

Other Rinnai Tankless codes

CodeMeaning
17Venturi blockage
18Gas valve air/fuel adjustment limit reached
19Electrical grounding / DC circuit short
21PC board data transfer error
22Gas valve adjustment fault
25Condensate pump failure or clogged drain
31Burner thermocouple out of range
32Outlet water temperature thermistor fault
33Heat exchanger thermistor fault
34Combustion air thermistor (Non-SENSEI) / Lime detecting thermistor (RX/CX)
35Tank temperature sensor fault
38Exhaust gas temperature sensor (CO sensor on RH180)

All Rinnai Tankless Water Heater error codes →

Rinnai code 30: homeowner questions

What does Rinnai code 30 mean?

Flammable vapor sensor activated or faulty. The flammable vapor sensor has tripped or failed; flammable vapors may be present near the water heater.

Is it safe to keep using my tankless water heater with code 30?

No. Code 30 is a safety shutdown, so keep the tankless water heater off until a licensed technician has checked it.

Can I reset Rinnai code 30 myself?

Do not keep resetting it. Repeated resets can hide a safety problem; a licensed technician needs to find the cause.

Who can fix Rinnai code 30 near me?

Aurora Star Tech Inc. repairs Rinnai tankless water heaters in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.

Homeowner help: Tankless Water Heater No Hot Water: What to Check

Troubleshooting guides

Source: Rinnai Troubleshooting TWH Diagnostic Codes (100000652), p.35. Written in our own words as a summary; always check the original manual.

General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.

Emergency HVAC Service

647-657-2977