Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 04-53480147-01
Printed in U.S.A.
Form IIK-CRECOMZR74-04
Pg 1
9-21 Replaces: IIK-CRECOMZR74-03
Installation Instructions
Part No: CRECOMZR074A01 and CRECOMZR075A01
CONTENTS
Page
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . 1
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Vertical Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Horizontal Installation . . . . . . . . . . . . . . . . . . . . . . . . . 6
Barometric Hood Assembly . . . . . . . . . . . . . . . . . . . . 7
• BAROMETRIC HOOD (VERTICAL CONFIGURATION)
Vertical and Horizontal Applications . . . . . . . . . . . . . 8
Wiring Instructions for 1 and 2 Speed Units . . . . . . 9
EconoMi$er X System . . . . . . . . . . . . . . . . . . . . . . . . 13
• USING THE KEYPAD WITH SETTINGS AND
SETUP AND CONFIGURATION . . . . . . . . . . . . . . . . 19
W7220 Economizer Module Wiring . . . . . . . . . . . . . 19
Timeout and Screen Saver . . . . . . . . . . . . . . . . . . . . 20
HH79AH001 Dry Bulb Sensor . . . . . . . . . . . . . . . . . . 20
Enthalpy Settings (Enthalpy Optional) . . . . . . . . . . 20
Enthalpy Control Sensor Configuration . . . . . . . . . 21
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Cooling, Unit with EconoMi$er X System . . . . . . . . 22
Heating with EconoMi$er X System . . . . . . . . . . . . 22
Demand Controlled Ventilation (DCV) . . . . . . . . . . . 23
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . 23
Power Loss (Outage or Brownout) . . . . . . . . . . . . . 23
Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Clearing Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
SAFETY CONSIDERATIONS
Installation of this accessory can be hazardous due to system
pressures, electrical components, and equipment location (such as
a roof or elevated structure). Only trained, qualified installers and
service technicians should install, start-up, and service this
equipment.
When installing this accessory, observe precautions in the
literature, labels attached to the equipment, and any other safety
precautions that apply:
• Follow all safety codes
• Wear safety glasses and work gloves
• Use care in handling and installing this accessory
It is important to recognize safety information. This is the safety-
alert symbol:
. When you see this symbol on the unit and in
instructions or manuals, be alert to the potential for personal
injury.
Understand the signal words DANGER, WARNING, CAUTION,
and NOTE. These words are used with the safety-alert symbol.
DANGER identifies the most serious hazards which
will
result in
severe personal injury or death. WARNING signifies hazards
which
could
result in personal injury or death. CAUTION is used
to identify unsafe practices, which
may
result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which
will
result in enhanced installation, reliability,
or operation.
GENERAL
The EconoMi$er
®
X system utilizes the latest technology
available for integrating the use of free cooling with mechanical
cooling for packaged rooftop units. The solid-state control system
optimizes energy consumption, zone comfort, and equipment
cycling by operating the compressors when the outdoor-air
temperature is too warm, integrating the compressor with outdoor
air when free cooling is available, and locking out the compressor
when outdoor-air temperature is too cold. Demand control
ventilation is supported.
This EconoMi$er X system can be used with 1, 2, or 3 speed
(48/50LC 14) units.
CAUTION
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care and
wear appropriate protective clothing, safety glasses, and
gloves when handling parts and servicing rooftop units.
CAUTION
Failure to follow this caution may result in personal injury and
damage to the unit. Cover the duct opening as a precaution so
objects cannot fall into the return duct opening. Be sure to
remove the cover when installation is complete.
WARNING
Electrical shock can cause personal injury and death. Shut off
all power to this equipment during installation. There may be
more than one disconnect switch. Tag all disconnect locations
to alert others not to restore power until work is completed.
Medium Rooftop Units
12.5 to 27.5 Tons
Ultra Low Leak EconoMi$er
®
X Accessory
