Honeywell THE PA404 IS A SERIES 40 (2-WIRE, PSST) PROPRIETRESS CONTROLLER FOR USE IN 24, 120, 240 or 277 VOLT CONTROL CIRCUITS OR IN SELF-POWERED (MILLILITER) APPLICATIONS. UJ The PA404A iz a pressure actuated high limit, safety control for steam heating boilers; it breaks an electrical circuit to shut down the burner if steam pressure rises above a safe level. 0 The PA404B is used with suspension-type unit heaters to make the fan circuit when a pressure rise indicates the presence of steam.
MODELS: PA4O4A Proprietress Controller. Pressure-actuated safety control. Available with additive or subtraction differentials. PA4O4B Proprietress Controller. Pressure-actuated fan control, Additive differential. MAXIMUM OPERATING PRESSURE: 20 psi. MAXIMUM AMBIENT TEMPERATURE: 150 F. ELECTRICAL RATING (amperes): 120V AC Full Load 8.0 Locked Rotor 2.0 amp at 24V ac; 0.25 amp at 1/4 to 12V de. 480 5.1 30.6 8.3 FINISH: Gray enamel.
MOUNTING The PA404A must be located above the water line in a stern boiler, either adjacent to a pressure gauge or in another location recommended by the boiler manufacturer. See Fig. 1. All models are equipped with 2 terminals located on the switch, inside the cover. A wiring hole is provided for cinch rigid or flexible conduit, All wiring must comply with local electrical codes. See Figs. 3, 4, and 5 for typical wiring connections.
pain REFERENTIAL Bran : sim 4 ADDITIVE DIFFERENTIAL » “Switch Action” in Table 1. 10 SET THE PA404A WITH ATTRACTIVE DIFFERENTIAL 1. Set main scale indicator at desired cutout point turning main scale set point screw unt} indicator {sow Fig. 8) corresponds to pressure at which electric t should break. The recommended minimum set int is the differential setting plus 1-1/2 psi. 2.
