Siemens 194-2043 ROOM THERMOSTAT, PNEU, DA, FAHRENHEIT, DSP, DAY/NIGHT, 2-PIPESiemens 194 2043 Room Thermostat, Pneu, DA, Fahrenheit, DSP, Day Night, 2 pipe This Powerstar Retroline Day Night Retrostat Pneumatic Room Thermostat Chassis is a 2 pipe, Dual Set Point, Direct Acting, Day 15 psi, Night 20 psi with a Fahrenheit scale. Replaces Johnson Controls T 4506 201, T 4506 202, T 4506 203, T 4506 204. Additional Information Mounting2 pipe DisplayDual Setpoint Operating rangeDay Night Measuring rangeFahrenheit