What is RV Water Heater DSI Fault? [Troubleshoot]

If you see a fault code that indicates a DSI fault, then your water heater is not working most likely because of no incoming gas.

Your DSI may fail because of these reasons:

  • control board issues
  • check valve
  • no airflow
  • no water in tank
  • bad ECO
  • faulty thermostat
  • Boiler Safety Circuit board is bad
  • out of gas

DSI is direct spark ignition which adds flame to the gas in your RV. FLT means fault.It is an improved way to light the pilot and shuts off gas flow if it is not ignited as a safety feature.

DSI control system turns off ignition once the room temperature is what you want.


You can fix it yourself

You can reset the water heater by pressing reset button.
Note you may hear a clicking sound, that is normal.

You will find it in the panel and will need a screw driver. Each RV is different so
get details from your owners manual.

  1. Check propane levels: Ensure that you have an adequate propane supply in your RV’s propane tanks. If the propane level is low or empty, refill the tanks and try the water heater again.
  2. Inspect propane connections: Make sure that all propane connections are secure and free of leaks. Check the propane regulator for any signs of damage or malfunction.
  3. Reset the water heater: Turn off the water heater’s power switch, wait for a few minutes, and then turn it back on. This may reset the ignition system and clear the DSI fault.
  4. Clean the burner assembly: Dirt, rust, or debris on the burner assembly can cause ignition issues. Carefully remove the burner assembly and clean it with a soft brush, compressed air, or a vacuum cleaner. Inspect the burner for any signs of damage or corrosion, and replace it if necessary.
  5. Inspect the electrode and wiring: The electrode is responsible for creating the spark that ignites the propane burner. Check the electrode for proper positioning, damage, or wear. Ensure that the wiring connections are secure and free from corrosion or damage.
  6. Verify proper voltage: Use a multimeter to check the voltage at the water heater’s control board. Low voltage can cause ignition issues. Consult your owner’s manual for the correct voltage range.
  7. Check the control board: If all other components appear to be functioning correctly, there may be an issue with the water heater’s control board. Inspect the control board for any visible signs of damage or corrosion. If you’re unable to identify the issue, it may be necessary to replace the control board.


Here is a video showing how to do it:


You may have air in the line and it needs to be flushed out try running all stove burners for a minute to bleed it out.

A replacement control board will cost about $200.