Trane RLY1040 Relay 326058 755 High Accuracy: Precise regulation makes High Accuracy: Precise regulation makes this unit ideal for pressure factor measurement and fixed factor billing applications always verify the specific model number (193 A 1) as it is specifically tapped for the 193 A series boiler water level control Use a multimeter to verify coil resistance across terminals and check for continuity across the normally closed (NC) and normally open (NO) contacts while the coil is energized with 24VAC allowing 24V control signals to switch higher current circuits or manage two separate outputs from a single input