Johnson Controls P74AA-1C Differential Pressure Control, SPST Close On Decrease In Differential Press,

Johnson Controls P74AA-1C Differential Pressure Control, SPST Close On Decrease In Differential Press,. The Johnson Controls (PENN) P74 Series Differential Pressure Controls sense differences in pressure between two points, for operating or limit controls. These are desinged to detect flow across chiller or water cooled condensor, or in a heating system, or in refrigeration compressors (sensing lube oil pressure differential).