If your furnace blower runs constantly but the burners won't ignite—or if the system is short cycling—you should test for continuity across the terminals

and UDZ-400 series gas-fired heaters

The M847D actuator is reversible

or 150A settings before snapping the core shut

This Polar White ADB requires a Dometic wall-mounted thermostat

Trane SEN0999 Temp Sensor 323080-701 If your furnace blower runsThe Trane SEN0999 is a high precision mixed air temperature sensor engineered for commercial and industrial air handling units. Featuring a 15 foot capillary tube, this sensor is designed to provide comprehensive average temperature readings across the duct cross section, preventing localized stratification from causing inaccurate system cycling. This OEM Trane replacement is critical for economizer control and maintaining discharge air setpoints