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Johnson Controls W43A Humidistat


The W43A Humidistat provides SPDT control for use on low or line voltage applications. It has a thermoplastic cover with Allen-head locking screw to discourage unauthorized tampering. The sensing element consists of carefully selected and processed human hair.

• Human Hair Sensing Element provides stable, accurate measurement
• 1/4 hp (6A) Rated Contacts permits direct operation of many fans in commercial applications
• High/Low Adjustable Knob Range Stops allows adjustments within a desired range

Select a link under the "item" tab below to order.

Cat #Type
PLT333-12RConcealed Adjustment Faceplate, Vertical Mounting
PLT333-9RConcealed Adjustment Faceplate, Horizontal Mounting
KNB26A-600RThermoplastic Push On Adjustment Knob
PLT51A-602RHumidistat Mounting Plate
Product W43A-14C Humidistat
Contact Ratings   120 VAC 208 VAC 240 VAC
Full Load Ampere 6.0 3.5 3.0
Locked Rotor Ampere 36.0 21.0 18.0
Pilot Duty 125 VA at 24/277 VAC
Measurement Range 0 to 70% RH
Differential Fixed at approximately 6% RH
Contact Action SPDT
Switch Snap-acting Contacts in a Dust-protected Enclosure
Sensing Element Selected Human Hair
Material Base 0.050 in (1.27 mm) Cold Rolled Steel
Cover Beige Thermoplastic
Fish Base Zinc Plate Dichromate Dipped
Cover Brown Markings on Gold Anodized Aluminum
Mounting Vertical or Horizontal 2 x 4 in. (51 x 102 mm) Wall Box
Wiring Terminals Large 8-32 x 1/4 in. Binder Head Screws
Minimum Ambient Temperature 40° (4.4°C)
Maximum Ambient Temperature 100°F (38°C)
Agency Listings UL Guide No. XAPX; File E6688
CSA Class No. 4813 02: File LR948
Dimensions (H x W x D) 4.71 x 2.96 x 2.94 in. (120 x 75 x 75 mm)
Shipping Weight 0.9 lb (0.4 kg)

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