Rinnai Error Code 25: Condensate Overflow
Warning: Your Rinnai water heater is displaying error code 25, indicating a condensate overflow issue. This is not an immediate safety risk, but it could lead to water damage if not addressed.
How to Fix Rinnai Code 25
- Step 1: Check the condensate drain line for clogs. If it's clogged, try clearing it with a wet/dry vacuum or a plumbing snake.
- Step 2: If the drain line is clear, check the condensate neutralizer for any signs of damage or failure. If it's faulty, you'll need to replace it.
- Step 3: If neither of these solutions works, there might be a problem with your water supply. Call a professional plumber to diagnose and fix the issue.
How to Reset Rinnai Code 25
- 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 25 Mean?
Error code 25 on your Rinnai water heater means that the condensate neutralizer is overflowing. This could be due to a clogged drain line, a faulty neutralizer, or a problem with the water supply. The system has shut down to prevent further issues, and you'll need to troubleshoot and fix the problem before it can resume normal operation.
Common Causes
- Clogged condensate drain line
- Faulty condensate neutralizer
- Problem with water supply (too hard or acidic water)
Diagnostic Steps
| If... | Check | Expected |
|---|---|---|
| Condensate drain line is clogged | Clear the drain line | Clear drain line, no overflow |
| Condensate neutralizer is damaged | Replace the neutralizer | No overflow after replacement |
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 |
|---|---|---|---|
| Condensate Neutralizer | RIN-10072400 | — | Find Part |
| Condensate Drain Line | — | — | — |
Related Codes on Same Models
Other codes that affect the same Rinnai model families as 25.
| 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 |
| 29 | Condensate Neutralizer | Warning |
| 31 | Inlet Thermistor Failure | Warning |
| 34 | Combustion Air Thermistor | Warning |