York YCUL0020, Installation, Operation And Maintenance Manual

Page: 143 / 178

JOHNSON CONTROLS
143
SECTION 8 – UNIT OPERATION
Form 150.63-NM9
Issue date: 5/20/2021
8
Figure 42 - YCUL0045 – YCUL0072 Fan Location (Typical)
Fan #1
Fan #2
Fan #3
Fan #4
LD07403A
Table 19 - YCUL0020 – YCUL0072 Condenser Fan Control Using Outdoor Ambient Temperature and Discharge
Pressure
(Discharge pressure controls will
not function
unless the optional discharge pressure transducer is installed)
Table 20 - YCUL0045 – YCUL0072 Condenser Fan Control Using Discharge Pressure Only
* NOTE: STEP 2 is not active in the “Standard Ambient” mode. When changing to “Low Ambient” control, fan power wiring also changes.
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
FWD
OAT >25°F (-3.9°C)
OR
DP > Fan Ctrl On Press
OAT < 20°F (-6.7°C)
AND
DP < Fan Ctrl On Press –
(Diff. Press.)
8M 11M TB7-9 TB10-9 3 4
*3
2 FANS
FWD
OAT >65°F (18.3°C)
OR
DP > Fan Ctrl On Press
+ 40 psig (2.76 barg)
OAT < 60°F (15.6°C)
AND
DP < Fan Ctrl On Press.-
[Diff. Press + 40 psig
(2.76 barg)]
7M &
8M
10M &
11M
TB7-8
&
TB7-9
TB10-8
&
TB10-9
1 & 3 2 & 4
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
FWD
DP > Fan Ctrl On
Press
DP < Fan Ctrl On Press –
(Diff. Press.)
8M 11M TB7-9 TB10-9 3 4
*3
2 FANS
FWD
DP > Fan Ctrl On
Press
+ 40 psig (2.76 barg)
DP < Fan Ctrl On Press.) –
[(Diff Press.) + 40 psig (2.76 barg)]
7M &
8M
10M
& 11M
TB7-8
&
TB7-9
TB10-8
&
TB10-9
1 & 3 2 & 4