527 01 2701 00
Specifications subject to change without notice.
35
Standard or Single Speed Fan Operation
FAN TYPE = 1SPEED is not used on RHW units.
2 Speed Fan Operation
The W7220 controller has the capability to work with a sys
-
tem using a 2 speed supply fan. The W7220 does not con
-
trol 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 11.
Table 11 — Fan Speed
The W (heating mode) is not controlled by the W7220 but it
requires the status to know where to position the OA damp
-
er 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. See Table 12.
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 cool
-
ing will be enabled through Y1 Out or Y2 Out.
Table 12 —
Economizer Operation - FAN TYPE = 2SPEED
*With stage 3 delay (STG3 DLY) in Advanced setup, COOL Y2-OUT will be turned ON after the delay time specified.
N/A = Not applicable
STATE
FAN SPEED
OCC
Low
Y1
Low
Y2
High
W
High
INPUTS
OUTPUTS
DEMAND
CONTROLLED
VENTILATION
(DCV)
OUTSIDE AIR
GOOD TO
ECONOMIZE
W
(HEAT ON)
COOL
Y1-IN
COOL
Y2-IN
COOL
Y1-OUT
COOL
Y2-OUT
FAN SPEED
(reference
only)
DAMPER POSITION
OCCUPIED
UNOCCUPIED
NONE
NO
ON
N/A
N/A
OFF
OFF
HIGH
MIN POS H
Closed
OFF
OFF
OFF
OFF
OFF
LOW
MIN POS L
Closed
OFF
ON
OFF
ON
OFF
LOW
MIN POS L
Closed
OFF
ON
ON
ON
ON
HIGH
MIN POS H
Closed
YES
ON
N/A
N/A
OFF
OFF
HIGH
MIN POS H
Closed
OFF
OFF
OFF
OFF
OFF
LOW
MIN POS L
Closed
OFF
ON
OFF
OFF
OFF
LOW
MIN POS L to
Full Open
Closed to
Full Open
OFF
ON
ON
ON
OFF*
HIGH
MIN POS H to
Full Open
Closed to
Full Open
Below CO
2
Set
NO
ON
N/A
N/A
OFF
OFF
HIGH
VENTMIN H
Closed
OFF
OFF
OFF
OFF
OFF
LOW
VENTMIN L
Closed
OFF
ON
OFF
ON
OFF
LOW
VENTMIN L
Closed
OFF
ON
ON
ON
ON
HIGH
VENTMIN H
Closed
YES
ON
N/A
N/A
OFF
OFF
HIGH
VENTMIN H
Closed
OFF
OFF
OFF
OFF
OFF
LOW
VENTMIN L
Closed
OFF
ON
OFF
OFF
OFF
LOW
VENTMIN L to
Full Open
Closed to
Full Open
OFF
ON
ON
ON
OFF*
HIGH
VENTMIN H to
Full Open
Closed to
Full Open
Above CO
2
Set
NO
ON
N/A
N/A
OFF
OFF
HIGH
VENTMIN H to
VENTMAX H
Closed
OFF
OFF
OFF
OFF
OFF
LOW
VENTMIN L to
VENTMAX L
Closed
OFF
ON
OFF
ON
OFF
LOW
VENTMIN L to
VENTMAX L
Closed
OFF
ON
ON
ON
ON
HIGH
VENTMAX H to
VENTMAX H
Closed
YES
ON
N/A
N/A
OFF
OFF
HIGH
VENTMIN H to
VENTMAX H
Closed
OFF
OFF
OFF
OFF
OFF
LOW
VENTMIN L to
VENTMAX L
Closed
OFF
ON
OFF
OFF
OFF*
LOW
VENTMIN L to
Full Open
Closed to
Full Open
OFF
ON
ON
ON
OFF*
HIGH
VENTMIN H to
Full Open
Closed to
Full Open
Summary of Contents for RHW036-060
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