THX9321/9421 Prestige® IAQ and RF EIM

With wireless accessories

® U.S. Registered Trademark.
Copyright © 2011 Honeywell International Inc.
All rights reserved.
SystemInstallation Guide
69-2490-03

Control for up to 4 Heat/2 Cool heat pump systems or up to 3 Heat/2 Cool

conventional systems for residential and commercial applications.

Installation guide for:

Quick start guide

• PrestigeTHX9321/9421thermostat
• EquipmentInterfaceModule(EIM)
• PortableComfortControl
• WirelessOutdoorSensor
• WirelessIndoorSensor
• RedLINK™InternetGateway
1 Install thermostat ..........................................................page 3
2 Install optional Equipment Interface Module (EIM) ................3
3 Power optional accessories ...................................................4
4 Link thermostat to wireless network ......................................5
5 Link optional accessories to wireless network ......................6
6 Install optional sensors ..........................................................7
7 Customize thermostat (installer options) ...............................8
Wiring guides ..................................................................10-17
Key features ....................................................................18-25
Device replacement and specifications ..........................26-27
DISCONNECT POWER BEFORE INSTALLATION. Can cause electrical shock or equipment damage.
MERCURY NOTICE: If this product is replacing a control that contains mercury in a sealed tube, do not place the old control
in the trash. Contact the Thermostat Recycling Corporation at www.thermostat-recycle.org or 800-238-8192 for information on how
and where to properly and safely dispose of your old thermostat.
Must be installed by a trai ned, experienced tech nician. Read these instructions carefully. Failure to follow
these instructions can damage the product or cause a hazardous condition.
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