York YCUL0065EE - TABLE 22 - YCUL0020 - YCUL0035 Low Ambient Condenser Fan Control - Discharge Pressure Control; TABLE 21 - YCUL0020 - YCUL0072 Low Ambient Condenser Fan Control - Discharge Pressure Control

JOHNSON CONTROLS
144
Form 150.63-NM9
Issue date: 5/20/2021
SECTION 8 – UNIT OPERATION
Condenser fan control - YCUL0020 – YCUL0072
Table 21 - YCUL0020 – YCUL0072 Low Ambient Condenser Fan Control – Discharge Pressure Control
FAN
STAGE
ON OFF
CONTACTOR
I/O BOARD
OUTPUT
FAN #
SYS 1 SYS 2 SYS 1 SYS 2 SYS 1 SYS 2
1
1 FAN
REV
DP > Fan Ctrl On
Press
DP < Fan Ctrl On Press
– Di󰀨. Press.
7M 10M TB7-8 TB10-8 1 REV 2 REV
2
1 FAN
FWD
DP > Fan Ctrl On
Press
+ 20 psig
(1.38 barg)
DP < Fan Ctrl On Press.) –
[Di󰀨 Press. + 20 psig
(1.38 barg)]
8M 11M TB7-9 TB10-9
3
FWD
4
FWD
3
2 FANS
FWD
DP > Fan Ctrl On
Press
+ 40 psig
(2.76 barg)
DP < Fan Ctrl On Press.) –
[Di󰀨 Press. + 40 psig
(2.76 barg)]
8M & 9M
11M &
12M
TB7-9
&
TB7-10
TB10-9
& TB10-10
1 & 3
FWD
2 & 4
FWD
Table 22 - YCUL0020 – YCUL0035 Low Ambient Condenser Fan Control – Discharge Pressure Control
FAN STAGE ON OFF CONTACTOR
I/O BOARD
OUTPUT
FAN #
Stage 1
"OAT > 25° F or
DP > ctrl_press"
"OAT < 20° F and
DP < ctrl_press - di󰀨_press"
7M TB7-8 1 REV
Stage 2
"OAT > 45° F or
DP > ctrl_press + 20
psig"
"OAT < 40° F and
DP < ctrl_press - di󰀨_press + 20
psig"
8M TB7-9 3 FWD
When Low Ambient Control of the fans is
selected, fan control will be by discharge
pressure only.