Economizer Module Wiring Diagrams - Honeywell Home THX9321 Prestige 2.0 Manual

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THX9321 PRESTIGE 2.0 AND THX9421 PRESTIGE

Economizer Module Wiring Diagrams

Typical wiring of a W7220 Economizer Module for a heat pump system, using a Prestige THX9321 thermostat or
Equipment Interface Module.
Fig. 351. Wiring a W7220 Economizer Module for a heat pump system.
Typical wiring of a W7220 Economizer Module for a conventional system, using a Prestige THX9321 thermostat or
Equipment Interface Module.
Fig. 352. Wiring a W7220 Economizer Module for a conventional system.
1 "A" or "L/A" terminal must be configured for Economizer in the installer setup (ISU 2220). These terminals are powered by
the cooling transformer (Rc terminal).
2 Terminal AUX 2 is present only on the Equipment Interface Module.
3 Connect the changeover valve from the roof top unit to the normally open contacts of an isolation relay to prevent feed-
back into the economizer module during defrost. If this is not done when the system goes into defrost, it will change the
economizer into cooling mode due to the feedback and open the outside damper while in heating mode.
68-0311—08
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IAQ WITH EIM
W7220 Economizer Module
(See wiring guidelines provided with the product)
AUX2-I
OCC
E-GND
AUX1-O
Y2-I
Y2-O
Y1-I
Y1-O
C
R
Transformer
VAC
W7220 Economizer Module
(See wiring guidelines provided with the product)
AUX2-I
OCC
E-GND
AUX1-O
Y2-I
Y2-O
Y1-I
Y1-O
C
R
Transformer
VAC
O/B
3
3 1
O/B L/A
1
R
120 24
C
VAC
A
1
R
120
24
C
VAC
150
Rooftop Unit
Y1 Y2 AUX AUX 2 G
Y Y2 AUX AUX 2 G
2
Thermostat/EIM
MCR34808
Rooftop Unit
Y1 Y2 W1 W2 G
Y Y2 W W2 G
Thermostat/EIM
MCR34810