3
* CRENTDIF004A00 accessory is used on many different base units. As
such, these kits may contain parts that will not be needed for installation.
†
33ZCSENCO2 is an accessory CO
2
sensor.
** 33ZCASPCO2 is an accessory aspirator box required for duct-mounted
applications.
††
CRBDIOX005A00 is an accessory that contains both 33ZCSENCO2
and 33ZCASPCO2 accessories.
GENERAL
See Table 1 for Package Usage and Contents.
The EconoMi$er IV system utilizes the latest technology available
for integrating the use of free cooling with mechanical cooling for
packaged rooftop units. The solid-state control system optimizes
energy consumption, zone comfort, and equipment cycling by
operating the compressors when the outdoor-air temperature is too
warm, integrating the compressor with outdoor air when free
cooling is available, and locking out the compressor when
outdoor-air temperature is too cold. Demand controlled ventilation
is supported.
The EconoMi$er IV system utilizes gear-drive technology with a
direct-mount spring return actuator that will close upon loss of
power. The EconoMi$er IV system comes standard with an
outdoor air temperature sensor, supply air temperature sensor, and
low temperature compressor lockout switch. (See Fig. 1.) Return
air temperature, indoor enthalpy and outdoor enthalpy sensors are
available for field installation. Field-installed CO
2
sensors are
available. (See Table 2.)
Barometric relief dampers provide natural building pressurization
control. Barometric relief dampers are built into the design and are
standard. An optional power exhaust system is available for
applications requiring even greater exhaust capabilities. The
power exhaust set point is adjustable at the EconoMi$er IV
controller. See Table 2 for sensor usage.
Fig. 1 — EconoMi$er IV Component Locations
Table 2 — EconoMi$er IV Sensor Usage
APPLICATION
ECONOMI$ER IV WITH
OUTDOOR AIR DRY BULB SENSOR
Accessories Required
Carrier and Bryant
units
ICP units
Outdoor Air Dry
Bulb
None. The outdoor air dry bulb sensor is factory
installed.
Single Enthalpy
HH57AC078
AXB078ENT
Differential
Enthalpy
HH57AC078 and
CRENTDIF004A00*
AXB078ENT and
CRENTDIF004A00*
CO
2
for DCV
Control using
a Wall-Mounted
CO
2
Sensor
33ZCSENCO2
†
CO
2
for DCV
Control using
a Duct-Mounted
CO
2
Sensor
33ZCSENCO2 and 33ZCASPCO2**
or
CRCBDIOX005A00
††
Outside Air
Damper
Economizer
Actuator
Low Temp.
Lockout
Wiring
Harness
EconoMi$er IV
Controller
Outside Air
Temp (OAT)
Sensor
Return Air Damper
