Honeywell Thermal Solutions FSG L4079B1058 Pressure and Limit Controller

Honeywell Thermal Solutions FSG L4079B1058 Pressure and Limit Controller delivers precise protection for boilers, air handling units and process lines. This differential-pressure switch uses a diaphragm-type operator to monitor pressure changes and trigger a safe shutoff on rise, ensuring reliable safety interlocks in demanding environments. Designed for air, gas, and fluid media, it operates from 5 to 50 PSI with a 10 PSI differential, making it ideal for system protection and limit control.

UL approved, with SPST 2-circuit contact configuration, this controller handles 120 VAC full-load ratings of 9.8 A and 58.8 A locked rotor, or 240 VAC full-load 4.9 A and 29.4 A locked rotor. It features a 1/4 inch female threaded connection and offers surface-mount or 1/4 inch female threaded mounting. The unit operates at up to 150°F and uses manual reset with break on pressure rise to ensure a safe, immediate shutdown when needed. Its compact footprint measures 4-1/2 W x 3-1/2 D x 5 H.

• Type: Differential pressure with diaphragm-operated actuator
• Operating range: 5–50 PSI; Differential: 10 PSI
• Media: Air, gas, or fluid
• Contacts: SPST, 2 circuits; 120 VAC full-load 9.8 A, locked rotor 58.8 A; 240 VAC full-load 4.9 A, locked rotor 29.4 A
• Connections: 1/4" female thread
• Mounting: 1/4" female threaded or surface mount
• Safety and approvals: UL approved
• Reset and operation: Manual reset, break on pressure rise
• Temperature rating: Up to 150°F