Off-Cycle Defrost control - PENN Controls - A421ABD - A421AED - Electronic Temperature Control - A421 Off‐Cycle Defrost Model

A421 Series Electronic Temperature Controls with Off-Cycle Defrost Installation Guide

PENN Controls
Product name
A421 Off‐Cycle Defrost Model
Document type
Installation Guide
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Document revision
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You can use the A421 Control with Off-Cycle Defrost to set up regular, passive defrost periods of 1 minutes to 99 minutes. The defrost interval can range from 2 hours to 24 hours, or you can set it to 0 for no defrost interval. You can also start or stop a defrost cycle in the following two ways: use the three-button touchpad on the Advanced Menu or connect a momentary switch to the binary input (BI).

The A421 with Defrost Control is typically used to provide temperature control and adjustable, timed, passive defrost cycles on medium temperature cooling applications such as reach-in boxes, display cases, and walk-in coolers.