Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
PC 111
Catalog No. 534-80004
Printed in U.S.A.
Form 48/50-56SI
Pg 1
1-01
Replaces: 48/50-49SI
Book 1 1 1 4 4 4
Tab
1a 1b 5a 5a 6a 6b
Cancels: IIK 548-36-33
IIK 548-36-35
1/15/01
Installation Instructions
Part Numbers: CRECOMZR--004A01, CRECOMZR--005A01
CRECOMZR--006A01, CRECOMZR--007A01
TABLE OF CONTENTS
Page
GENERAL
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1,2
ACCESSORIES
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
SAFETY CONSIDERATIONS
. . . . . . . . . . . . . . . . . . . . . . 2
VERTICAL ECONOMI$ER INSTALLATION
. . . . . . 2-5
HORIZONTAL ECONOMI$ER
INSTALLATION
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
ACCESSORY INSTALLATION
. . . . . . . . . . . . . . . . . . 7-12
Accessory Hinged Panels
. . . . . . . . . . . . . . . . . . . . . . . . 7
Standard Hood
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Power Exhaust Hood
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Auxiliary Sensors
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Actuator Auxiliary Switch Adjustment
. . . . . . . . . . . 11
COMMISSIONING
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .12,13
CO
2
Control Set Up
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Mechanical Cooling Lockout
. . . . . . . . . . . . . . . . . . . . 12
Dry-Bulb Changeover Set Up
. . . . . . . . . . . . . . . . . . . . 12
Ventilation Air (Minimum Position
Set Up)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
START-UP
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13,14
Differential Enthalpy Switchover
Strategy
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Operating Sequence
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
TROUBLESHOOTING
. . . . . . . . . . . . . . . . . . . . . . . . . 14-16
LED Indication
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Manual Configuration Pushbutton
. . . . . . . . . . . . . . . 14
Sensor Characteristics
. . . . . . . . . . . . . . . . . . . . . . . . . . 14
GENERAL
The accessory EconoMi$er package uses microprocessor-
based controls to sequence mechanical cooling with cool out-
door air (free cooling) to satisfy the cooling load and minimize
energy consumption. Free cooling can be used alone or in con-
junction with mechanical cooling.
The standard economizer uses a dry bulb sensor to sense
Outdoor Air Temperature (OAT). This sensor provides two
functions for the EconoMi$er controller: it determines the
availability of free cooling (EconoMi$er changeover); and it
disables compressors at low ambient temperatures (mechanical
cooling lockout).
When free cooling is available, the EconoMi$er sequences
free cooling with up to two stages of mechanical cooling to
maintain comfort in the space. When free cooling is not avail-
able, the EconoMi$er modulates to an adjustable minimum
position set point to maintain a supply of fresh air entering the
building.
Barometric relief dampers provide natural building pressur-
ization control. An optional power exhaust system is available
for jobs requiring greater relief.
The microprocessor CO
2
input terminals allow the addition
of an accessory CO
2
sensor in the space or in return air duct-
work. When the EconoMi$er recognizes the presence of the
CO
2
sensor, a ventilation control strategy automatically begins
to operate. The outdoor air damper modulates open past mini-
mum position as the CO
2
level in the space increases over the
adjustable set point.
See Fig. 1 and 2 for EconoMi$er component locations. See
Table 1 for Package Usage and Contents.
Small Rooftop Products
Gas Heating/Electric Cooling,
Electric Cooling, and Heat Pump Units
3 to 12
1
/
2
Tons
Accessory EconoMi$er Package
with Power Exhaust and Auxiliary Sensors
BAROMETRIC RELIEF DAMPERS
CONTROLLER
ECONOMI$ER
PLUG
GEAR-DRIVEN
DAMPER
OUTDOOR AIR
TEMPERATURE
SENSOR
ACTUATOR
Fig. 1 — 3 to 6 Ton EconoMi$er
Component Locations
CONTROLLER
BAROMETRIC
RELIEF DAMPERS
OUTDOOR AIR
TEMPERATURE
SENSOR
GEAR-DRIVEN
DAMPER
ACTUATOR
ECONOMI$ER
PLUG
Fig. 2 — 7
1
/
2
to 12
1
/
2
Ton EconoMi$er
Component Locations
