Lefoo Air Differential Pressure Switch LF31A

Name: Air Differential Pressure Switch LF31A
Brand: LEFOO INDUSTRIAL CO.,LTD.
Rating: 4.8 (50 reviews)

LF31A switches offer pressure, vacuum, and differential models capable of sensing very low setpoints and switching current up to 5A resistive,2.5A inductive. Designed for use in the HVAC industry, where reliable air proving is critical to both performance and customer safety, the LF31 is a favourite with leading manufacturers of gas-fired warm air furnaces and water heaters.

Smaller and lighter than any other differential switch, the LF31 is built for the same temperature range and operating life as conventional switches made of stamped steel. The LF31 features a unique integral snap switch, with positive snap action and self-wiping silver contacts for ultra-reliable switching. The moulded silicone diaphragm converts very low pressure or vacuum into the movement of an actuator disk, which operates the silver alloy contacts.

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Specification
Features
Application

Specification of Air Pressure Switch LF31A

Model	LF31A
Medium	Air, products of combustion or natural gas
Operating Pressure Range	0.08" W.C. to 34" W.C.
Mounting Position	Diaphragm in any vertical Plane
Proof Pressure	100" W.C. (3.6PSI)
Burst Pressure	5psi Minimum
Operating Temperature	-40° C to 85° C
Contact Arrangement	SPST or SPDT
Electric Rating	Resistance: Initial: <50 milliohms Current: 100mA minimum, 5A (resistive) maximum (fine silver alloy contacts); 15mA minimum, 0.2A maximum (gold-platinum-silver alloy contacts);
Terminals	6.3mm copper alloy
Connection	Φ6.4mm for tube connection
Agency Approval	UL353, CE( EN1854: 2006, 13611: 2000)

Conversion: 1"W.C.(inch water column)= 1 inch/H2O=249Pa 1mbar=100Pa

Features of Air differential Pressure Switch

1. Low OEM unit cost, robust design, setpoint accuracy, and high reliability.

2. Self-wiping silver contacts for ultra-reliable switching.

3. Pressure, vacuum, and differential models capable of sensing very low setpoints.

Application of Air Differential Pressure Switch

The pressure switch control can be used in many types of equipment.

HVAC industry, where reliable air proving is critical to both performance and customer safety, and gas-fired warm air furnaces and water heaters.

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