Invensys Thermostat Manual Model Fd Apr 2026

Turn the bypass adjustment screw (marked 'B') until the flame is stable across the entire burner. : Calibration is done manually on the face of the unit.

Turn the thermostat to "OFF" and wait five minutes for any accumulated gas to escape. Invensys Thermostat Manual Model Fd

To adjust: light the main burner and set the dial to 300°F. Once the temperature is constant, turn the dial back to the lowest setting. Turn the bypass adjustment screw (marked 'B') until

: For digital models, prying the front cover off and removing batteries for 5 minutes often performs a hard reset. To adjust: light the main burner and set the dial to 300°F

: If you have a digital Invensys model (like the 9000 series) rather than the mechanical FD, "LO" typically indicates a low battery or that the room temperature is below 30°F.

: Ensure the red button is held down for at least one minute after lighting to engage the thermocouple.

For detailed installation diagrams, you can refer to the Robertshaw VC4200 Commercial Installation Guide or the Invensys Heating and Cooling Basics Manual .