Watch us troubleshoot this unusual Firefly G7A failure on an Airstream Interstate.

The furnace and AC were running continuously without a command from the control panel. After troubleshooting the system, we found the Firefly system was sending a 12V signal out to the appliances when it shouldn’t have been, causing them to run without being commanded.

This is a great example of why understanding the control signals and troubleshooting the Firefly multiplex system is important when dealing with strange RV electrical problems.

If you’re troubleshooting a Firefly G7/G7A system, furnace or AC running without a command, or appliances receiving an unwanted 12V signal, this video may help you track down the problem