Johnson Controls YORK Tempo YLAA Series, Installation Operation & Maintenance

Page: 162 / 192

JOHNSON CONTROLS
162
FORM 150.72-NM1 (1020)
Unit Operation
TABLE 18 – YLAA STANDARD CONDENSER FAN CONTROL USING DISCHARGE PRESSURE ONLY
(5 OR 6 FANS PER SYSTEM)
FAN
STAGE
ON* OFF**
IPUII I/O OUTPUT FAN CONTACTOR FAN #
SYS 1 SYS 2 SYS 1 SYS 2 SYS 1 SYS 2
1
DP >
PROGRAMMED
FAN CONTROL
ON PRESSURE
DP <
PROGRAMMED
FAN CONTROL
ON PRESSURE
MINUS
PROGRAMMED
DIFFERENTIAL
PRESSURE
TB7-8 TB10-8 1-KF1 2-KF1 1-MF1 2-MF1
2
DP >
PROGRAMMED
FAN CONTROL
ON PRESSURE &
FAN STAGE 1 IS
ENERGIZED
DP <
PROGRAMMED
FAN CONTROL
ON PRESSURE
MINUS
PROGRAMMED
DIFFERENTIAL
PRESSURE &
FAN STAGE 1
IS ENERGIZED
TB7-8 &
TB7-9
TB10-8 &
TB10-9
1-KF1 &
1-KF2
2-KF1 &
2-KF2
1-MF1 &
1-MF2 &
1-MF3
2-MF1 &
2-MF2 &
2-MF3
3
DP >
PROGRAMMED
FAN CONTROL
ON PRESSURE
AND FAN
STAGES 1 & 2
ARE ENERGIZED
DP <
PROGRAMMED
FAN CONTROL
ON PRESSURE
MINUS
PROGRAMMED
DIFFERENTIAL
PRESSURE &
FAN STAGES
1 & 2 ARE
ENERGIZED
TB7-8 &
TB7-9 &
TB7-10
TB10-8 &
TB10-9 &
TB10-10
1-KF1 &
1-KF2 &
1-KF3
2-KF1 &
2-KF2 &
2-KF3
5 FAN:
1-MF1 &
1-MF2 &
1-MF3 &
1-MF4 &
1-MF5
6 FAN:
1-MF1 &
1-MF2 &
1-MF3 &
1-MF4 &
1-MF5&
1-MF6
5 FAN:
1-MF1 &
1-MF2 &
1-MF3 &
1-MF4 &
1-MF5
* When a fan stage is turned on, the pressure for the next stage is increased 20 PSIG and ramped back to the programmed on pressure over
the next 20 seconds.
** When a fan stage is turned off (Programmed ON pressure minus the differential), the OFF pressure for the next stage is decreased 20 PSIG
and ramped back to the programmed OFF pressure minus the differential.
The time delay (fan delay timer) be -
tween turning fan stages on and off is
fixed at 5 seconds.