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The A421 Series Electronic Temperature Controls are single-stage controls with a single-pole, double-throw (SPDT) output relay.

A421 Controls feature a bright backlit LCD with adjustable brightness and a three-button touchpad interface that can be set up to restrict user adjustments. An LED indicates the output relay's On/Off status. Standard A421 Series control modules have simple On and Off temperature settings for heating or cooling, an adjustable anti-short cycle delay, temperature setback, and sensor offset capability. The temperature control range is -40 to 212°F or -40 to 100°C.

Low-Voltage Type 4X Electronic Temperature Control: Type 4X (NEMA), IP67 weathertight enclosure for surface-mount applications. Rated for 24 VAC Class 2, Safety Extra Low Voltage (SELV). Includes an A99BB-25C temperature sensor with 9-7/8 in. (0.25 m) cable.
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Product Type:
Temperature Control
Enclosure Type:
Supply Voltage:
24 VAC Class 2
Lead Wire Length:
9-3/4 Inches
Temperature Control
Min Temp (F):
Max Temp (F):
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