Rinnai Error Code 72: Flame Rod Detection
Warning: Your Rinnai water heater is experiencing a flame rod detection issue, which has caused it to shut down for safety reasons. It's important to address this issue promptly to prevent further damage or potential hazards.
How to Fix Rinnai Code 72
- Step 1: Locate the reset button on your water heater and press it to reset the system. If the error persists, proceed to the next step.
- Step 2: Check the gas supply to your water heater. Ensure the gas valve is open and the gas supply is turned on at the main gas supply valve.
- Step 3: If the issue persists, it's best to call a professional HVAC technician to diagnose and repair the problem.
How to Reset Rinnai Code 72
- Turn off the unit using the power button on the front panel.
- Turn off the gas supply valve.
- Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
- Restore power at the breaker, then open the gas valve.
- Turn the unit back on. If the error returns, the underlying issue needs repair.
Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.
What Does Rinnai Error Code 72 Mean?
The Rinnai 72 error code indicates a problem with the flame rod, a crucial safety component in your water heater. The flame rod monitors the burner's ignition and flame stability. When the system detects an issue with the flame rod, it shuts down the burner to prevent potential gas leaks or other hazards. Common causes for this error include a faulty flame rod, a clogged flame arrester, or a problem with the gas supply.
Common Causes
- Faulty flame rod
- Clogged flame arrester
- Gas supply issue (low pressure or no gas)
- Faulty gas control valve
Diagnostic Steps
| If... | Check | Expected |
|---|---|---|
| The system displays error code 72 | Inspect the flame rod for any signs of damage or wear | The flame rod should be clean and undamaged |
| The flame rod appears to be in good condition | Check the gas supply pressure at the inlet of the gas control valve | The gas supply pressure should be within the manufacturer's specified range (usually between 7 and 11 inches W.C.) |
| Gas supply pressure is within the specified range | Inspect the flame arrester for clogs or damage | The flame arrester should be clean and undamaged |
Applicable Rinnai Models
- CU(gas)
- HE(dual_fuel)
- HE++ Series(gas)
- I-SERIES(gas)
- NCB(gas)
- NPE(gas)
- RE(gas)
- REP(gas)
- RL(gas)
- RU(gas)
- RUCS(gas)
- RX(gas)
- RXP(gas)
- Rinnai NCB Series(gas)
- Rinnai NPE Series(gas)
- Rinnai R Series(gas)
- Rinnai RL Series(natural_gas)
- Rinnai RU Series(natural_gas)
- Rinnai RUR Series(gas)
- Rinnai VSP(gas)
- V(gas)
Replacement Parts
| Part | OEM Number | Est. Cost | Where to Buy |
|---|---|---|---|
| Flame Rod | RIN-1100010000 | — | Find Part |
| Flame Arrester | RIN-1100020000 | — | Find Part |
| Gas Control Valve | RIN-1100030000 | — | Find Part |
Related Codes on Same Models
Other codes that affect the same Rinnai model families as 72.
| Code | Description | Severity |
|---|---|---|
| 02 | Stagnant Water Detection | Warning |
| 10 | Air Supply/Exhaust Blockage | Warning |
| 11 | No Ignition | Warning |
| 12 | Flame Failure | Warning |
| 14 | Thermal Fuse | Warning |
| 16 | Over-Temperature | Warning |
| 19 | Electrical Grounding | Warning |
| 25 | Condensate Overflow | Warning |
| 29 | Condensate Neutralizer | Warning |
| 31 | Inlet Thermistor Failure | Warning |