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EconoMi$er X (Factory--Installed Option)
EconoMi$er X is an ultra low leak economizer system
which is available for 48LC 07 units.
The factory--installed option consists of:
S Low leak economizer damper assembly
S Direct--drive damper actuator with local equipment bus
communications
S W7220 economizer controller with keypad and display
S Supply Air Temperature sensor (20K ohm)
S Outdoor changeover condition sensor (either 20K ohm
dry--bulb or enthalpy sensor)
Unit Installation —
All damper hardware and standard economizer control
components except the enthalpy sensor are factory--mounted
in their operating location. Complete the unit installation by
relocating the enthalpy sensor (when provided; see below),
then assembling and mounting the unit’s outside air hood.
Refer to the base unit’s installation instruction manual for
directions on locating the hood parts package and
assembling the hood with filters.
Enthalpy Sensor Relocation —
See Fig. 51 for view of the enthalpy sensor. Locate the
enthalpy sensor on the side of the economizer housing;
remove mounting screws and save screws. Confirm the DIP
switches are set at OFF, OFF, OFF (see Table 13). Move the
enthalpy sensor to the front face of the economizer housing
and mount per label.
W7220 Economizer Controller
The economizer controller used on electro mechanical units
is the Honeywell W7220.
The W7220 provides typical economizer functions,
including:
S Management of outside air damper for base unit
Occupied (damper open and modulating) and unit OFF
or Unoccupied status (damper closed)
S Free--cooling using all outside air when outdoor
conditions permit Integrated cooling operation using
outside air and mechanical cooling when required
S Demand Control Ventilation (DCV) for modulating
ventilation airflow according to space CO
2
level
(requires factory--option or field--installed CO
2
sensor)
The W7220 control also includes a new capability that will
adjust the damper control points during DCV or minimum
ventilation operation as the indoor fan speed is changed.
This control function ensures that required space ventilation
airflow quantities are maintained during reduced fan speed
operation.
Additional control capabilities include automatic detection of
new sensors and detection of sensor failure or loss of
communication.
The W7220 control module includes an integral user
interface with keypad and LCD display that permits direct
input of setpoint values and configurations and display of
status and alarms.
The W7220 controller is located in the RTU base unit’s
Control Box. See the Installation Instructions for this base
unit for the location of the Control Box access panel.
User Interface —
The user interface consists of a 2--line LCD display and a
4--button keypad on the front of the economizer controller.
2 LINE
LCD
MENU UP
(EXIT)
BUTTON
SCROLL
UP/DOWN
BUTTONS
SELECT
(ENTER)
BUTTON
C11548
Fig. 43 -- W7220 Controller
Keypad —
The four navigation buttons (see Fig. 43) are used to scroll
through the menus and menu items, select menu items,
and to change parameter and configuration settings.
Using the Keypad with Menus —
To use the keypad when working with menus:
S Press the
(Up arrow) button to move to the previous
menu.
S Press the
(Down arrow) button to move to the next
menu.
S Press the
(Enter) button to display the first item in
the currently displayed menu.
S Press the
(Menu Up/Exit) button to exit a menu’s
item and return to the list of menus.
The Menus in display order are:
S STATUS
S SETPOINTS
S SYSTEM SETUP
S ADVANCED SETUP
S CHECKOUT
S ALARMS
48HC48LC
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