LEFOO LF25 Steam Pressure Switch
LEFOO LF25 is a manufacturer-documented pressure control switch, distinct from an analog transmitter.
AirAlign engineering comparison and selection cautions
Manufacturer lists six steam setpoint ranges 0.2–0.6 to 5–9bar, but proof rating is only 3bar for its first two low ranges and 10bar for the other four. Do not substitute one range or proof class for another. Diaphragm snap-action design, SPST/SPDT choice, stated maximum +125°C, 16(4)A at 250VAC contact data and factory setpoint are options requiring supplier confirmation. Check which models and revisions the manufacturer-listed CE and TÜV documents cover.
Configuration and approval checklist
Original primary source: LEFOO LF25 manufacturer product and technical document section.
Related Pages
LEFOO manufacturer profile · Pressure Switches
Verified LF25 Technical & Application Selection
Why the proof-pressure tier matters
Specifying an LF25 using only the largest published 9 bar actuation band is unsafe: the two low-pressure diaphragms are published with just 3 bar proof pressure. Pressure proof and switching cut-out are different limits, and the installed pressure vessel still needs its independent pressure-protection design.
Steam and heater integration
Steam-cleaning cycles introduce high temperature, condensate and electrical switching stresses. Confirm the medium temperature at the diaphragm, terminal temperature, factory cut-in/out setting and contact duty before using LF25 to switch a heater or motor directly. The manufacturer describes engineering-stage setpoint selection and a factory setting for production; do not promise full field recalibration.
Approval scope
LEFOO publishes LF25 TÜV and CE documents at the original LF25 page. Match their covered order codes and standard conditions. Neither document automatically certifies a complete steam cleaner, nor covers every selected equipment configuration.
LF25 — steam proof pressure by range
LF25 offers multiple steam pressure setpoint bands, but the lower two range variants have different published proof-pressure ratings than the higher four. Those pressure classes must not be mixed when specifying boiler or steam equipment. Verify wetted diaphragm, steam temperature exposure and appropriate pressure impulse connection, and require any mandatory independent boiler safety device separately. Check the contact’s electrical switching duty and cut-in/cutout direction during commissioning.