What is the difference between S66AA-1 and S66AA-1C

Streamlined Installation: Compact angleway design with 31-inch capillary tube and included bulb strap for thermal response stabilization

Featuring a direct mount configuration

internal wear usually indicates a need for a rebuild kit rather than a new electrical coil

York S1-025-37015-000 Wiring Harness THPU32HP7Y What is the difference betweenThe York S1 025 37015 000 Wiring Harness is a critical OEM interface adapter designed to bridge communication and power between HVAC control boards and auxiliary components with mismatched pin configurations. As a high performance 4 pin to 6 pin wiring adapter, this harness is essential for field retrofits and repairs where a multi pin transition is required to maintain signal integrity. Built to Source 1 specifications, it eliminates the need for