York MILLENNIUM YCAS, Installation Operation & Maintenance

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141
YORK INTERNATIONAL
FORM 201.18-NM2
8.4 CONDENSER FAN CONTROL
The chiller is equipped with 8 or 10 condenser fans,
with 4 or 5 fans per system as given below. Fan control
is via Outside Ambient Temperature (OAT) and Dis-
charge Pressure (DP). There are six stages of fan con-
trol utilizing 3 outputs per system. The fan stages will
work according to Table 2 or Table 3 depending on the
number of fans/system. There will be a minimum 5 sec-
ond delay between all fan stages.
Condenser fan ON conditions are governed solely by
the Discharge Pressure (DP). When the DP rises above
15.2 bar, Stage 1 is activated. From here, subsequent
fan stages are activated as the DP rises in increments
of 1 bar, except stage 6, which is activated when the
DP rises over 20 bar. The system will remain at the
Fan
ON OFF
Fan Wire
Relay
Stage
Fans Conditions Conditions
Contactor Number
Board
DP DP & OAT
Output
1 1 >15.2 BAR <10.3 BAR & <15.6ºC 9M 130 15
S
2 3 >16.2 BAR <11.4 BAR & <18.3ºC 10M 131 14
Y
3 5, 7 >17.2 BAR <12.4 BAR & <21.1ºC 11M, 12M 132 10
S
4 1, 5, 7 >18.3 BAR <13.4 BAR & <23.9ºC 9M, 11M, 12M 130, 132 10,15
5 3, 5, 7 >19.3 BAR <14.5 BAR & <26.7ºC 10M, 11M, 12M 131, 132 10, 14
1
6 1, 3, 5, 7 >20.0 BAR <15.2 BAR & <29.4ºC 9M, 10M, 11M, 12M 130, 131, 132 10, 14, 15
1 2 >15.2 BAR <10.3 BAR & <15.6ºC 15M 230 15
S
2 4 >16.2 BAR <11.4 BAR & <18.3ºC 16M 231 14
Y
3 6, 8 >17.2 BAR <12.4 BAR & <21.1ºC 17M, 18M 232 10
S
4 2, 6, 8 >18.3 BAR <13.4 BAR & <23.9ºC 15M, 17M, 18M 230, 232 10,15
5 4, 6, 8 >19.3 BAR <14.5 BAR & <26.7ºC 16M, 17M, 18M 231, 232 10, 14
2
6 2, 4, 6, 8 >20.0 BAR <15.2 BAR & <29.4ºC 15M, 16M, 17M, 18M 230, 231, 232 10, 14, 15
TABLE 2 – CONDENSER FAN CONTROL & FAN CONTACTOR DATA FOR DXST UNITS WITH 4 FANS/SYSTEM
Fan
ON OFF
Fan Wire
Relay
Stage
Fans Conditions Conditions
Contactor Number
Board
DP DP & OAT
Output
1 1 >15.2 BAR <10.3 BAR & <15.6ºC 9M 130 15
S
2 3, 5 >16.2 BAR <11.4 BAR & <18.3ºC 10M, 11M 131 14
Y
3 7, 9 >17.2 BAR <12.4 BAR & <21.1ºC 12M, 13M 132 10
S
4 1, 7, 9 >18.3 BAR <13.4 BAR & <23.9ºC 9M, 12M, 13M 130, 132 10,15
5 3, 5, 7, 9 >19.3 BAR <14.5 BAR & <26.7ºC 10M, 11M, 12M, 13M 131, 132 10, 14
1
6 1, 3, 5, 7, 9 >20.0 BAR <15.2 BAR & <29.4ºC 9M, 10M, 11M, 12M, 13M 130, 131, 132 10, 14, 15
1 2 >15.2 BAR <10.3 BAR & <15.6ºC 15M 230 15
S
2 4, 6 >16.2 BAR <11.4 BAR & <18.3ºC 16M, 17M 231 14
Y
3 8, 10 >17.2 BAR <12.4 BAR & <21.1ºC 18M, 19M 232 10
S
4 2, 8, 10 >18.3 BAR <13.4 BAR & <23.9ºC 15M, 18M, 19M 230, 232 10,15
5 4, 6, 8, 10 >19.3 BAR <14.5 BAR & <26.7ºC 16M, 17M, 18M, 19M 231, 232 10, 14
2
6 2, 4, 6, 8, 10 >20.0 BAR <15.2 BAR & <29.4ºC 15M, 16M, 17M, 18M, 19M 230, 231, 232 10, 14, 15
TABLE 3 – CONDENSER FAN CONTROL & FAN CONTACTOR DATA FOR DXST UNITS WITH 5 FANS/SYSTEM
FIGURE 44 – CONDENSER FAN LAYOUT FOR DXST 2-COMPRESSOR UNITS
highest fan stage reached unless the OFF conditions
given in the next paragraph are satisfied.
Condenser fan OFF conditions are governed by both
the DP and OAT. Fan staging will be decreased from
the highest stage reached if both the DP and OAT re-
quirements are met. For example, if a system is at a fan
stage of 4, and the DP falls under 13.4 bar and the OAT
drops below 23.9ºC, the fan stage will be reduced to 3.
The OFF conditions are given in the next two tables.
The tables on the next page also present fan contactor
data for the fans involved in each fan stage. SYS 1 uses
relay board #1. SYS 2 uses relay board #2.
YCAS 0373, 0403, 0453, 0503, 0543 and 0573 models
have 4 condenser fans/system:
9