If your Suburban SF-style furnace runs for a while and then shuts off, there may be a problem with the gas supply, especially if the regulator or gas fittings were recently replaced.

In this troubleshooting video, I’ll show you an interesting issue we found on this customer’s RV. The customer had replaced the regulator and used Teflon tape on a flare fitting. In this application, using Teflon tape on a flare fitting can cause problems, including reduced gas pressure under load. I’ll explain what we found and show you why proper gas pressure is important for reliable furnace operation.

If your furnace starts normally but shuts down before completing a heating cycle, checking the regulator, gas pressure, and flare fittings is a good place to start.