Rinnai Code 11: No Ignition on a Rinnai Tankless

The Short Answer: On a Rinnai tankless, code 11 means “No Ignition”: the heater tried to light and never detected a flame. The owner checks Rinnai lists are simple: make sure the gas is on at the heater, the meter or the cylinder, and that a propane tank isn’t empty. Everything else on Rinnai’s list, from air in the gas line to the igniter, is work for a licensed professional.

What Rinnai’s manuals say

Every current Rinnai owner manual we checked, including the Sensei manual (opens in a new tab), lists code 11 as No Ignition (Heater Not Turning On). The remedy list is the same in substance across Sensei, RE/VE and Value Series models. Rinnai’s Value Series manual (opens in a new tab) shades most of the list as “licensed professional only”, which is a clear way to split it:

Rinnai’s service manual (opens in a new tab) applies code 11 to Sensei, Sensei RX/CX and non-Sensei models. For Sensei models its first steps match the owner list (verify all gas valves are open and check the propane tank), and next it has the technician verify that air was purged from the gas lines after installation.

When code 11 usually appears

• Right after installation. New gas piping often still holds air, which is why “bleed all air from gas lines” is on Rinnai’s list. That’s installer work, so call the installer back.
• After the gas was shut off. A meter swap, a gas leak repair or an unpaid bill can leave the gas off or partly closed at the meter or a branch valve.
• On propane. An empty or nearly empty tank, or a closed tank valve. Rinnai’s service manual also has the technician check that the propane tank is sized for the heater and that inlet pressure holds with the heater on high fire.
• After working fine for years. Gas supply is still the first thing to rule out. If the gas is fine, the cause is usually inside the heater: the igniter, flame rod, gas valve or a loose connection. The service manual notes that a loose (“floating”) flame rod can cause code 11 or 12.

What you can check safely

1. Make sure the gas valve on the pipe to the heater is fully open, with the handle in line with the pipe.
2. Check that other gas appliances (stove, furnace, dryer) work. If none do, call the gas utility.
3. On propane, check the tank gauge and that the tank valve is open.
4. Check that the heater’s power cord is plugged into its outlet and the outlet has power.
5. Restart once: close all hot taps, turn the heater off with the On/Off button on the controller, turn it back on, and open a hot tap. Rinnai doesn’t publish a separate reset for code 11; this is the controller’s normal off-and-on.

If 11 returns, stop there. Each ignition attempt sends some gas through the burner, and repeated restarts won’t fix a supply or ignition fault. Write down the code, the model number from the rating label, and what changed recently, then call your installer or Rinnai.

Code 11, 12 or 10?

• 11: the burner never lit.
• 12: it lit, then lost its flame. See Rinnai code 12.
• 10: air supply or exhaust blockage (on condensing models, also a full condensate trap). See Rinnai code 10.

Other brands use 11 differently. On a Rheem or Richmond tankless, code 11 means the gas shut-off valve isn’t fully open; see Rheem code 11. Noritz uses 11 for ignition failure; see Noritz code 11.

What the technician will check

The technician measures inlet gas pressure with the heater firing, confirms the gas type matches the heater, and checks whether the gas line and meter are large enough for the heater’s input. Inside the heater they check the igniter, the flame rod and its wiring, the gas valves, and the burner surface for moisture or debris. On condensing models they also check the condensate drain. If air in a new gas line is the cause, purging it is part of correcting the installation.

Frequently Asked Questions

Q: Does code 11 mean gas is leaking? A: No. It means the heater didn’t detect a flame when it tried to light. A gas smell is a separate emergency: if you notice one, don’t restart the heater; leave and call the gas utility from outside.

Q: Can I bleed the air out of the gas line myself? A: No. Rinnai lists it as licensed-professional work, and opening gas fittings is unsafe. If the heater is newly installed, the installer should come back to do it.

Q: Is code 11 covered by warranty? A: That depends on the cause. A gas supply or installation problem isn’t a defect in the heater; a failed igniter or gas valve may be a covered part. Rinnai’s FAQ (opens in a new tab) suggests contacting Rinnai or your installer with the code; Rinnai’s support line is 1-800-621-9419.