LEFOO LF55 Refrigeration Pressure Switch Family
OEM-specified LEFOO LF55 refrigeration pressure control switch for approved refrigerants / gases applications. Selection must match the exact version, operating conditions and signal output.
Model Identification & Specifications
Original Manufacturer Technical Information
OEM published variants LF5502–LF5542 have DIFFERENT adjustable pressure bands and safe max operating pressure, e.g. LF5502 −0.5…2bar with 16.5bar maximum, LF5532 8…32bar with 35bar maximum and LF5542 8…42bar with 46.5bar maximum. LF5506M/LF5530M require manual reset and should not replace automatic-reset control switches. Manufacturer text says maximum 42bar but model table specifies this is only LF5542, not all LF55. Original TÜV attestation N8A 111343 0007 Rev.00 covers LF55/LF55V under EN60730, 40T65 switch-head ambient and IP20 after mounted, and applies only to the named models and installation conditions.
Confirm pressure control versus safety-cutout role, manual reset versus automatic reset, rated pressure/temperature and actual refrigerant or steam medium. Select the correct process port, contacts, mounting enclosure and electrical locked-rotor rating for the compressor or pump. Confirm the correct order code, available model-specific imagery and relevant manufacturer compliance documents. Check manufacturer current order-code evidence before field installation.
Engineering Selection & Practical Interpretation
LF55 has family-specific static-pressure limits: LF5502 16.5 bar maximum, LF5532 35 bar, LF5542 46.5 bar. Manual-reset LF5506M/LF5530M cannot be blindly substituted for automatic restart models. Interpret the cited EN60730 and IP20 data only for the specified product and its mounted configuration.
Before using the switch as a protective device, verify how it responds at trip, reset and loss of supply, and whether a separate calibrated monitor is required. The contact wiring, allowable media and operating temperature must correspond to the original controller design. Select a documented variant instead of assuming that similarly named housings are interchangeable.
Installation and Integration
Differentiate threshold switching from continuous measurement. Confirm adjustment range, hysteresis, measurement reference and sample setup for the operating medium.
NO/NC/SPDT contact type and current are configuration-specific. Low-current reed or signal contacts require suitable control electronics rather than direct motor wiring.
Check approved media, temperature, fitting, mounting orientation, protection against surges and ingress performance at the supplied cable termination.
Conformity needs the exact serial/part option and certificate scope. A product-family marketing statement is not evidence that another configuration is explosion-protected.
Related Product Models
Related LEFOO model #4504 · Related LEFOO model #4507 · LEFOO manufacturer profile
Official Technical Resources
LF55 — refrigerant pressure control by code
LF55 is a refrigerant pressure-control switch family with different available pressure bands and potentially different low/high cutout behavior. Confirm compatibility with the actual refrigerant, pressure pulsations and process temperature. The normal fan/compressor control contact may not qualify as an independent safety high-pressure cutout. Setpoint, reset method and electrical rating must come from the exact LF55 variant rather than a generic family diagram.