Rinnai Error Code 17: Rinnai Code 17 - Exhaust or Intake Blockage

Severity
Warning
Type
digital display
Estimated repair cost: $250 — $600 (parts + labor)
Warning: Your Rinnai tankless water heater has shut down due to a potential exhaust or intake blockage. This requires troubleshooting to restore hot water.

How to Fix Rinnai Code 17

  1. Step 1: Visually inspect the exterior exhaust and intake vents for any obvious obstructions like leaves, snow, or ice. Clear away any debris you can safely reach.
  2. Step 2: Ensure that the vent termination is not damaged or crushed. If it is, contact a qualified technician.
  3. Step 3: If the error persists after clearing any visible obstructions, call a qualified HVAC technician to inspect the unit and venting system internally.

How to Reset Rinnai Code 17

  1. Turn off the unit using the power button on the front panel.
  2. Turn off the gas supply valve.
  3. Turn off the circuit breaker supplying power to the unit. Wait 30 seconds.
  4. Restore power at the breaker, then open the gas valve.
  5. 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 17 Mean?

Rinnai error code 17 indicates a problem with the venting system. Specifically, the unit's sensors have detected an obstruction in either the exhaust vent (where combustion gases leave the unit) or the intake vent (where fresh air enters for combustion). This is important because proper venting is needed for safe and efficient operation. If exhaust gases can't escape, they could potentially back up into your home. Also, the unit needs the correct air-to-fuel ratio to burn cleanly. When the control board detects a blockage, it shuts down the unit as a safety precaution. The unit will not operate until the blockage is cleared and the error code is reset. This protects you from potentially dangerous conditions and prevents damage to the unit.

Common Causes

  • Exhaust vent is blocked by debris (leaves, snow, ice, bird nest). This is the most common cause.
  • Intake vent is blocked by debris (leaves, snow, ice).
  • Vent termination is improperly installed or damaged, causing backpressure.
  • Internal blockage within the heat exchanger due to scale buildup (less common).
  • Faulty fan motor not providing adequate airflow (rare).

Diagnostic Steps

If... Check Expected
Unit displays error code 17 Visually inspect the exhaust and intake vents for obstructions. Vents are clear of debris.
Vents appear clear Use a manometer to measure the exhaust pressure at the test port on the unit. Pressure within the range specified in the Rinnai installation manual (typically a negative pressure).
Exhaust pressure is outside the specified range Inspect the vent run for kinks, sags, or improper slope. Vent run is properly installed and free of obstructions.
Vent run is clear Measure the fan motor voltage during operation. Voltage matches the rating on the fan motor label.

Applicable Rinnai Models

Replacement Parts

Part OEM Number Est. Cost Where to Buy
Fan Motor 256000031
Pressure Sensor
Vent Termination

Related Codes on Same Models

Other codes that affect the same Rinnai model families as 17.

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