Johnson Controls Penn A421ABC Series - User Manual

A421 Series Standard Electronic Temperature Controls Installation Instructions
Refer to the QuickLIT website for the most up-to-date version of this document.
1
Applications
The A421 Series Electronic Temperature Controls are
single-stage, electronic temperature controls with a
single-pole, double-throw (SPDT) output relay.
A421 controls feature a backlit LCD with adjustable
brightness and three-button touchpad interface that
can be set up to restrict user adjustments. An LED
indicates the output relay's On/Off status.
A421 controls 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
-40to212°F or -40to100°C.
The A421 controls are available either in Type1
(NEMA), IP20 (CE), high-impact plastic enclosures
suitable for surface or DIN rail mounting (Figure 1)
or in Type 4X (NEMA), IP66 (CE) watertight, corrosion
resistant surface mount enclosures (Figure 2).
Dimensions
IMPORTANT: Use this A421 Series Electronic
Temperature Control only as an operating control.
Where failure or malfunction of the A421 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 control.
IMPORTANT: Utiliser ce A421 Series Electronic
Temperature Control uniquement en tant que
dispositif de régulation. Lorsqu'une défaillance ou un
dysfonctionnement du A421 control risque de
provoquer des blessures ou d'endommager
l'équipement contrôlé ou un autre équipement, la
conception du système de contrôle doit intégrer des
dispositifs de protection supplémentaires. Veiller
dans ce cas à intégrer de façon permanente
d'autres dispositifs, tels que des systèmes de
supervision ou d'alarme, ou des dispositifs de
sécurité ou de limitation, ayant une fonction
d'avertissement ou de protection en cas de
défaillance ou de dysfonctionnement du
A421 control.
Figure 1: A421 Control with Type 1 (NEMA),
IP20 Enclosure Dimensions, in. (mm)
Figure 2: A421 Control with Type 4X (NEMA),
IP66 Enclosure Dimensions, in. (mm)
A421 Series Standard Electronic Temperature
Controls
Installation Instructions
A421ABC-x, A421AEC-x,
A421GBF-x, A421GEF-x
Part No. 24-7664-3019, Rev. D
Issued March 2016

Johnson Controls Penn A421ABC Series Specifications

General

Type	Electronic Temperature Control
Output Type	Relay
Control Mode	On/Off
Control Action	Heating or Cooling
Temperature Range	-40°F to 212°F (-40°C to 100°C)
Mounting	surface mount
Display	LED
Agency Listings	CE
Outputs	SPDT Relay
Sensor Type	Thermistor

Summary

Product Overview and Specifications

Applications and Safety

Details the intended use and important safety precautions for the A421 control.

Physical Dimensions

Provides diagrams and measurements for Type 1 and Type 4X enclosures.

Installation Procedures

Mounting Guidelines

Covers general and specific mounting instructions for Type 1 and Type 4X enclosures.

Wiring Connections

Explains terminal block functions, wire types, and power supply configurations.

Control Configuration and Operation

Front Panel Interface

Describes the LCD display, buttons, and status indicators on the control's front panel.

Parameter Setup and Adjustment

Details how to configure temperature settings, delays, failure modes, and other operational parameters.

Menu Navigation

Guides users through accessing and modifying control parameters using the three-button interface.

Troubleshooting and Fault Resolution

Fault Code Interpretation

Lists and explains fault codes displayed on the LCD, with corresponding solutions.

Operational Troubleshooting

Provides step-by-step procedures for diagnosing and resolving common operational issues.

Ordering and Technical Details

Product Selection Guide

Offers tables to help select the correct A421 model and compatible A99 sensors.

Technical Specifications

Lists comprehensive electrical, environmental, and performance data for the controls.