DIY Error Codes

Rinnai Tankless water heater Code 11

The heater tried to light and could not.

Make sure the gas is on and a propane tank is not empty. If it still shows 11, call a licensed gas pro.

Start the fix →When to call a pro ↓
Full answer & models

Rinnai code 11 means: No Ignition. Make sure the gas is on and a propane tank is not empty. If it still shows 11, call a licensed gas pro.

Applies to: SENSEI™ SeriesNon-SENSEI™ Series
Also searched as: Rinnai code 11, Rinnai error 11, Rinnai error code 11

If you smell gas, leave the building and call your gas supplier from a neighbor's phone. Do not touch switches or use any phone inside.
Why
If you smell gas: do not try to light any appliance, do not touch any electrical switch, and do not use any phone in your building. Leave and call your gas supplier from a neighbor's phone; if you cannot reach them, call the fire department. Rinnai states that only trained and qualified professionals may follow its diagnostic-code service instructions, and that power, gas and water must be turned off before servicing. Never operate the heater with any vent pipe disconnected. Do not adjust the internal gas valve. Burn hazard (Rinnai): hot exhaust and vent may cause serious burns; keep small children and animals away, and hot water outlet pipes can be hot to touch.

What 11 means

The heater tried to light and could not.

More detail
Rinnai's diagnostic-code guide (page 14) titles code 11 "No Ignition". Rinnai's guide is written for trained, qualified professionals, so this page lists only the owner-level checks and tells you when to stop.

5-minute checks

Fix it step by step

Step 1 of 2

  1. Check that the gas is on

    • 2 min
    • None
    • DIY

    Safety: If you smell gas, leave the building and call your gas supplier from a neighbor's phone. Do not touch switches or use any phone inside.

    Gas valves open; propane tank not empty.

    More detail

    Check that the gas is on.

    Rinnai's guide: verify all gas valves on the system are open and, on propane, that the tank has gas in it.

    Did the code clear?

  2. Call a licensed pro

    • Decision
    • None
    • Pro decision

    Stop here and book a qualified technician.

    More detail

    Call a licensed pro.

    Rinnai's other code 11 steps (gas pressure, igniter and flame rod tests, gas type parameters, venting) require someone qualified to service gas systems.

    Still showing 11?Need a pro → call a pro

Code cleared. Nice work.

Watch the display for a day to make sure it stays clear.

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Fixed after any step? Watch the display for a day to make sure it stays clear. Still 11 after step 2? call a pro.

Call a pro if…

  • Gas is on and code 11 returns.
  • The heater was just installed or converted between gas types.
  • You smell gas.

FAQ

What does Rinnai code 11 mean?

No ignition, per Rinnai's diagnostic guide.

Source: Rinnai, Troubleshooting Tankless Water Heater Diagnostic Codes (100000652), page 14. Written by the DIY Error Codes team. Updated 2026-10-16. DIY Error Codes is independent and not affiliated with or endorsed by Rinnai.