ICP RHH120, Руководство по установке

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Specifications subject to change without notice.
516 01 3604 04
*With 2SP FAN DELAY (Advanced Setup Menu) when in the economizing mode there is a delay for the high speed fan to try to satisfy the call for
second stage cooling by turning on the fan to high and opening the OA damper 100% before the first stage mechanical cooling is enabled.
†
With stage 3 delay (STG3 DLY) in Advanced setup menu, second stage of mechanical cooling Y2-O can be turned on after the delay if the calls for
Y1-I and Y2-I have not been satisfied.
Fig. 49 — Single Enthalpy Curve Boundaries
ENTHALPY SETTINGS
When the OA temperature, enthalpy and dew point are be
-
low the respective setpoints, the Outdoor Air can be used
for economizing. Figure 49 shows the new single enthalpy
boundaries in the W7220. There are 5 boundaries (set -
points ES1 through ES5), which are defined by dry bulb
temperature, enthalpy and dew point.
Refer to Table 22 for ENTH CURVE setpoint values.
The W7220 calculates the enthalpy and dew point using the
OA temperature and humidity input from the OA enthalpy
sensor. When the OA temperature, OA humidity and OA
dew point are all below the selected boundary, the
economizer sets the economizing mode to YES, economiz -
ing 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.
Figure 49 shows the 5 current boundaries. There is also a
high limit boundary for differential enthalpy. The high limit
boundary is ES1 when there are no stages of mechanical
cooling energized and HL (high limit) when a compressor
stage is energized.
Table 21 — Enthalpy Operation, with Demand Controlled Ventilation (DCV) (CO
2
Sensor) — 2 Speed Fan
DCV
OUTSIDE AIR
GOOD TO
ECONOMIZE?
Y1-I Y2-I FAN SPEED Y1-O Y2-O OCCUPIED UNOCCUPIED
Below Set
No
Off Off Low 0-v/Off 0-v/Off VENTMIN L Closed
On Off Low 24-v/On 0-v/Off VENTMIN L Closed
On On High 24-v/On 24-v/On VENTMIN H Closed
Yes
Off Off Low 0-v/Off 0-v/Off VENTMIN L Closed
On Off Low 0-v/Off 0-v/Off VENTMIN L to Full-Open Closed to Full-Open
On On High 24-v/On 0-v/Off
†
VENTMIN H to Full-Open Closed to Full-Open
Above Set
No
Off Off Low 0-v/Off 0-v/Off VENTMIN L to VENTMAX Closed
On Off Low 24-v/On 0-v/Off VENTMIN L to VENTMAX Closed
On On High 24-v/On 24-v/On VENTMIN H to VENTMAX Closed
Yes
Off Off Low 0-v/Off 0-v/Off VENTMIN L to VENTMAX Closed
On Off Low 0-v/Off 0-v/Off VENTMIN L to Full-Open Closed to Full-Open
On On High
DELAY*
24-v/On
0-v/Off
†
VENTMIN H to Full-Open Closed to Full-Open
ECONOMIZING
AVAILABLE
NOT AVAILABLE
ENTHALPY
RA
HUM (%RH)
RA
TEMP
TEMPERATURE
ABSOLUTE HUMIDITY
ES5 ES4 ES3 ES2 ES1 HL
P1
(T,RH)
P2 (T,RH)
SINGLE ENTHALPY
DUAL ENTHALPY
HIGH LIMIT
Table 22 — Single Enthalpy and Dual Enthalpy High Limit Curves
ENTHALPY
CURVE
TEMP. DRY
BULB (F)
TEMP.
DEWPOINT (F)
ENTHALPY
(btu/lb/da)
POINT P1 POINT P2
TEMP. (F)
HUMIDITY
(%RH)
TEMP. (F)
HUMIDITY
(%RH)
ES1
80 60 28.0 80 36.8 66.3 80.1
ES2 75 57 26.0 75 39.6 63.3 80.0
ES3
70 54 24.0 70 42.3 59.7 81.4
ES4 65 51 22.0 65 44.8 55.7 84.2
ES5
60 48 20.0 60 46.9 51.3 88.5
HL 86 66 32.4 86 38.9 72.4 80.3