This is a complete troubleshooting guide on Rinnai Tankless Water Heater Code 11. Let’s check the 7 reasons at a glance that cause the unit to pop up the fault code 11:
- Gas supply to the unit may turn off
- Incorrect gas type or wrong inlet gas pressure
- Air in the gas lines
- Wires leading to PC board gets damaged
- Loose flame rod wire
- Loose or floating flame rod
- Dirty to defective igniter
The best part is- I will walk you through every troubleshooting step to fix those 7 culprits to clear the error message.
So, let’s get started.
Table of Contents
- What Does Error Code 11 Mean On Rinnai Tankless Water Heater?
- Rinnai Tankless Water Heater Code 11 [7 Easy Solutions]
What Does Error Code 11 Mean On Rinnai Tankless Water Heater?
Error code 11 indicates a problem with the ignition system (no ignition). Your Rinnai Tankless water heater will throw this fault code due to insufficient gas or incorrect inlet gas pressure, defective igniter, and dirty flame rod.
Besides, air in the gas line, loose or damaged flame rod wire, incorrect gas orifice, and blocked condensate line are some culprits that can cause the error code 11.
To erase the error message, you must troubleshoot all the issues I mentioned and fix them. The next chapter will walk you through every troubleshooting step to solve this water heater issue.
Rinnai Tankless Water Heater Code 11 [7 Easy Solutions]
This chapter will introduce you to the all possible culprits responsible for the error code 11. Nonetheless, I will walk you every troubleshooting step to fix those issues.
01. Gas Supply May Turn Off
You can’t ignite your gas tankless water heater without fuel. If you don’t turn on gas at the unit, meter, or cylinder, your water heater won’t get any fuel for combustion. And when you try to ignite the unit without turning on the gas supply, the unit will throw the error code 11.
How To Fix:
First off, check the gas control valve at the unit. Ensure you turn it counterclockwise to let the gas supply to the unit. On the other hand, if you have a propane tank, make sure the valve on the tank is at the on position.
02. Incorrect Gas Type or Wrong Inlet Gas Pressure
Rinnai Tankless Water Heater is operated either with natural gas or propane gas. If you use the wrong type of gas, you will never ignite the unit. Similarly, the inlet gas pressure should be within limits. Otherwise, it will cause error code 11.
How To Fix:
Check the manual and ensure you use the right type of fuel. If the unit requires natural gas for operation, power up the water heater with gas. Otherwise, connect your water heater with the propane line.
Next, ensure there is correct inlet gas pressure at the unit. On a Rinnai gas tankless water heater, the gas supply pressure should be between 3.5” WC to 10.5” WC. On the other hand, the inlet gas pressure on a propane unit should be between 8” WC to 13.5” WC.
I highly suggest you call a qualified technician if the gas supply pressure goes out of range.
03. Air In The Gas Lines
Before turning on your tankless water heater, you should purge all the gas lines. If there is dirt or air in the gas lines, your water heater will not work properly. Sometimes, air in the water lines can also affect the water flow and it prevents the unit from lighting. And guess what, it will cause the unit to pop up the error message 11.
How To Fix:
Generally, a tankless water heater will purge the line in seconds with the high gas flow. What I recommend you is- open the service valve and leave your water heater until you clearly smell the gas. Once you smell the gas, close the service valve and wait another few minutes before connecting the gas line to the water heater.
Bleeding air from water lines is also a must if you want to operate the unit trouble-freely. Just turn on the hot water faucets slowly and run the faucets for several minutes to allow the air to pass through the water pipe. Keep the hot water faucets opened until no more air bubbles are coming out of the faucet.
04. Wires Leading To PC Board Gets Damaged
If the wirings leading to the PC board come loose or get damaged, the unit can throw an error code 11. You can find five different electric connectors on your Rinnai tankless water heater. Check wires on each connector and look for visual damage.
How To Fix:
It will be best if you call a certified electrician to inspect the wiring leading to the PC board. If needed, you may need to replace the wiring or the PC board itself. The following tutorial will come into play for PC board installation:
05. Loose Flame Rod Wire
Ignition failure is a result of loose wiring to the flame rod. If the wires of the flame rod gets damaged or disconnected, you will fail to ignite your tankless water heater. Turns out, plugging the flame rod wire into the proper flame rod can cause the unit to pop up the code 11.
How To Fix:
Again, I recommend you call a professional to inspect the flame rod wiring of the unit. If needed, he will replace the flame rod wiring or the flame rod itself.
06. Loose Flame Rod
A loose or floating flame rod on your Rinnai tankless water heater will cause an ignition issue. It should be tight in its mounting brackets.
How To Fix:
Firstly, remove the upper access panel of the unit. Then, locate the flame rod and verify it is tight in the mounting bracket. You will never move it with your fingers if the gasket is intact. If loose, pull out the flame rod and clean it if needed. Then, reinstall it with a new gasket.
07. Dirty or Defective Igniter
An igniter is what helps to ignite the water heater. If this component gets dirty or defective, your water heater won’t ignite. As a result, it will showcase the error message 11 on the controller display.
How To Fix:
Turn off the unit and remove the access panel by unscrewing four nuts. Then, locate the igniter and clean it if there forms build up. If cleaning the igniter brings no luck for you, you must replace it. And this video will help you in this case:
Rinnai Tankless Water Heater will display the error code 11 if the gas isn’t turned on at the unit, gas meter, or tank. Turns out, defective igniter, loose flame rod, and air in the gas line can cause the code 11 problem.
Fortunately, I already broke down the reason behind this issue and what troubleshooting steps you should take. So, follow the guideline and clear the error message from the display.
If the error code returns after trying out all the steps I mentioned, I bet there is something critical. So, turn off the unit and call a professional to handle this issue for you.
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Eric Alvarez is an HVAC guy based in El Paso, Texas, United States. He obtained his Bachelor of Science degree from the University Of Texas at El Paso. Years of experience in the HVAC field have taught him many lessons, not the least of which is that the value of quality and knowledge far exceeds any promised initial savings. He has a good standing reputation for superior skills in heating, air conditioning, hot water tanks, and indoor air quality systems.