Applications - PENN Controls - LIT-12012249 - A421ABT - A421AET - Electronic Temperature Control - A421 Duty‐Cycle/Ventilation Models

A421 Series Electronic Temperature Controls with Cycle Timer Product Bulletin

Product name
A421 Duty‐Cycle/Ventilation Models
Document type
Product Bulletin
Document number
Revision date
Important: Use this A421 Series Electronic Temperature Control only as an operating control. Where failure or malfunction of the A421 Series Control could lead to personal injury or property damage to the controlled equipment or other property, additional precautions must be designed into the control system. Incorporate and maintain other devices, such as supervisory or alarm systems or safety or limit controls, intended to warn of or protect against failure or malfunction of the A421 Series Control.

You can use the A421 equipped with cycle timer in agricultural and related applications where free-cooling and ventilation are necessary. See Table 1 for application information by control type.

Table 1. Applications by A421 control type
Control Enclosure Application Wholesale Agricultural Chillers Data center Economizer Food service HVAC  Ice machines Process Refrigeration Ventilation
A421ABT Type 1 Cycle timer   X         X   X   X
A421AET Type 4X Cycle timer   X         X   X   X