PRODUCT DATA

68-0173- 3
® U.S. Registered Trademark
Copyright © 2001 Honeywell • All Rights Reserved
Perfect Climate Comfort Center™Control System

GENERAL

This document contains information on the Perfect Climate
Comfort Center™ Control System including components and
accessories. Some components and accessories include the
PC8900A Control Panel, W8900A-C Remote Module,
C7189A Remote Indoor Sensor, C7089A Outdoor Sensor,
C7100A Discharge Air Sensor, CO2 Monitor, CM8900A
Communication Module, and W8735B Telephone Access
Module.
The Comfort Center control system provides 24 Vac energy
saving control for a heating and cooling system, while
providing reliable and precise temperature, ventilation and
humidity control.

FEATURES

The PC8900A mounts in the living space and accurately
measures and controls room temperature and humidity.
• Only four wires required for installation.
• Large, continuously lit LCD.
• Seven-day (auto copy) programming.
• Simultaneous display of heat and cool setpoints.
• Keyboard lockout protection available.
• No batteries required, indefinite program retention.
• Circulation fan setting improves indoor air quality.
• Field configurable for:
— Automatic or manual changeover.
— °F or °C display.
— 12- or 24-hour clock.
— Adaptive Intelligent Recovery™ control or conven-
tional recovery.
— Humidity control in heating or cooling.
— Outdoor, remote, and discharge temperature sen-
sors available.
— Fan overrun in cooling.
— Ventilation control.
The W8900A-C mounts near the equipment. The
PC8900A, heating, cooling, ventilation and
dehumidification equipment and all additional sensors
are wired to the W8900A-C.
• Compatible with most 24 Vac Systems.
• Remote sensor, discharge sensor, outdoor sensor and
CO2 monitor available.
• Optional remote communications available.
PC8900A
W8900A-C

Contents

General ............................................................................. 1
Features ........................................................................... 1
Specifications .................................................................... 2
Ordering Information ........................................................ 2
Installation ........................................................................ 5
Wiring Diagrams ............................................................... 9
W8900A,C Hookup Diagrams ....................................... 9
W8900B Hookup Diagrams ........................................... 14
W8900A,B,C Humidity Control Hookup Diagrams ........ 18
Installer Setup ................................................................... 24
Programming PC8900A .................................................... 27
Checkout .......................................................................... 33
Operation .......................................................................... 34
Troubleshooting ................................................................ 40
Glossary ........................................................................... 44