Digital Thermostat A421 Series NEMA 4x 120V/240V

The A421 Series control is a single stage, electronic temperature control thermostat with a single-pole, double-throw (SPDT) output relay and a NEMA 4X IP66 housing.

Features:

• Single Stage
• SPDT output relay
• Easy-to-Read LCD temperature display
• Lockable front-panel display for set up and adjustment
• 120/240V
• Can display both Farenheit and Celsius measurments
• Includes an A99BB-25C temperature sensor with 9-7/8 inch (0.25 m) cable. Ambient operating temperature range: -40 to 212ºF (-40 to 100ºC)
• Longer sensor cable options are available in related
  products below

Applications:

The A421 Electronic Temperature Control can be used to control a wide variety of single-stage refrigeration or HVAC equipment. Sample temperature control applications include:

• temperature monitoring and alarming
• on/off control of boilers and chillers
• boiler and chiller pump control
• heating or cooling control
• cooling tower fan control based on water temperature
• supply, makeup, and mixed air temperature control
• temperature actuated valve control
• supply and makeup air damper and fan control
• condenser fan control based on condenser temperature

A421 Series Thermostat Installation & Operation Manual