Bryant 580J*04A, Руководство по установке

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Enthalpy Settings — When the OA temperature, enthalpy and
dew point are below the respective setpoints, the outdoor air
can be used for economizing. Figure 41 shows the new single
enthalpy boundaries in the W7220. There are 5 boundaries
(setpoints ES1 through ES5), which are defined by dry bulb
temperature, enthalpy and dew point.
Refer to Table 23 for ENTH CURVE setpoint values.
The W7220 calculates the enthalpy and dew point using the
OA temperature and humidity input from the OA enthalpy sen-
sor. When the OA temperature, OA humidity and OA dew
point are all below the selected boundary, the economizer sets
the economizing mode to YES, economizing is available.
When all of the OA conditions are above the selected
boundary, the conditions are not good to economize and the
mode is set to NO.
Fig. 41 shows the 5 current boundaries. There is also a high
limit boundary for differential enthalpy. The high limit bound-
ary is ES1 when there are no stages of mechanical cooling en-
ergized and HL (high limit) when a compressor stage is ener-
gized.
Table 23 provides the values for each boundary limit.
Two-Speed Fan Operation
NOTE: Two-Speed Fan operation does not apply to 580J 04-
06 units.
The W7220 controller has the capability to work with a sys-
tem using a 2-speed supply fan. The W7220 does not control
the supply directly but uses the following input status to
determine the speed of the supply fan and controls the OA
damper to the required position, see Table 24.
Table 24 — Fan Speed
The W (heating mode) is not controlled by the W7220 but it
requires the status to know where to position the OA damper
for minimum position for the fan speed.
The 2-speed fan delay is available when the system is pro-
grammed for 2-speed fan (in the System Setup menu item).
The 2-speed fan delay is defaulted to 5 minutes and can be
changed in the Advanced Setup menu item. When the unit has
a call for Y1 In and in the free cooling mode and there is a call
for Y2 In, the 2-speed fan delay starts and the OA damper will
modulate 100% open, the supply fan should be set to high
speed by the unit controller.
After the delay one of two actions will happen:
• The Y2–In call will be satisfied with the damper 100%
open and fan on high speed and the call will turn off
OR
• If the call for additional cooling in the space has not been
satisfied then the first stage of mechanical cooling will
be enabled through Y1 Out or Y2 Out.
Checkout
Inspect all wiring connections at the Economizer module’s
terminals, and verify compliance with the installation wiring
diagrams.
For checkout, review the Status of each configured parame-
ter and perform the Checkout tests.
NOTE: See Interface Overview on page 24 for information
about menu navigation and use of the keypad.
Power Up — After the W7220 module is mounted and wired,
apply power.
Initial Menu Display — On initial start up, Honeywell dis-
plays on the first line and Economizer W7220 on the second
line. After a brief pause, the revision of the software appears on
the first line and the second line will be blank.
Power Loss (Outage or Brownout) — All setpoints and ad-
vanced settings are restored after any power loss or interrup-
tion.
NOTE: All settings are stored in non-volatile flash memory.
Status — Use the Status menu (see Table 13) to check the pa-
rameter values for the various devices and sensors configured.
NOTE: See Interface Overview on page 24 for information
about menu navigation and use of the keypad.
Checkout Tests — Use the Checkout menu (on page 29) to test
the damper operation and any configured outputs. Only items
that are configured are shown in the Checkout menu.
NOTE: See Interface Overview on page 24 for information
about menu navigation and use of the keypad.
To perform a Checkout test:
1. Scroll to the desired test in the Checkout menu using
the ▲ and ▼ buttons.
2. Press the button to select the item.
3. RUN? appears.
4. Press the
button to start the test.
5. The unit pauses and then displays IN PROGRESS.
6. When the test is complete, DONE appears.
7. When all desired parameters have been tested, press the
(Menu Up) button to end the test.
The Checkout tests can all be performed at the time of in-
stallation or at any time during the operation of the system as a
test that the system is operable.
Troubleshooting
Alarms — The Economizer module provides alarm messages
that display on the 2-line LCD.
NOTE: Upon power up, the module waits 60 minutes before
checking for alarms. This allows time for all the configured
devices (e.g. sensors, actuator) to become operational. The
exception is the SAT sensor which will alarm immediately.
If one or more alarms are present and there has been no key-
pad activity for at least 5 minutes, the Alarms menu displays
and cycles through the active alarms.
It is possible to navigate to the Alarms menu at any time.
STATE FAN SPEED
OCC Low
Y1 Low
Y2 High
W High
WARNING
Failure to follow this warning could result in personal
injury, property damage, or death.
Before performing service or maintenance operations on
unit, always turn off main power switch to unit and install
lock(s) and lockout tag(s). Unit may have more than one
power switch. Ensure electrical service to rooftop unit
agrees with voltage an amperage listed on the unit rating
plate.
If any wiring changes are required, first be sure to re-
move power from the economizer module before starting
work. Pay particular attention to verifying the power con-
nection (24 Vac).