16
Table 9 — 30GXN,R080-350 Condenser Fan Staging (Main Base Board Controlled) (cont)
LEGEND
*Proper rotation of these fans to be checked when compressor(s) is running.
See Fig. 8 for condenser fan locations when viewing from the control box
end.
NOTE: For 30GXN,R153, 163-350 units, fan relays Fan 1 and Fan 3 energize
Circuit A fans. Fan relays Fan 2 and Fan 4 energize Circuit B fans.
09DK AIR-COOLED CONDENSERS
09DK044 Units — The 09DK044 units have accessory provi-
sion for fully automatic intermediate-season head pressure
control through condenser fan cycling. Fan number 2 and 3
cycling is controlled by outdoor-air temperature through air
temperature switches (ATS) 1 and 2.
The air temperature switches are located in the lower
divider panel underneath the coil header. The sensing element
is exposed to air entering the no. 1 fan compartment through a
hole in the panel. Fan no. 1 is non-cycling.
The air temperature switch controls the fans as shown in
Table 10.
Table 10 — Air Temperature Switch Control
(09DK044 Units)
09DK054-094 — The capacity of an air-cooled condenser
increases with increased temperature difference (defined as
saturated condensing temperature minus entering outdoor-air
temperature) and decreases with decreased temperature differ-
ence. A drop in entering outdoor-air temperature results in a
lower saturated condensing temperature. When outdoor-air
temperature drops below the minimum temperature for stan-
dard units, additional head pressure control is required.
Model 09DK units have fully automatic intermediate-
season head pressure control through condenser fan cycling
using electromechanical fan cycling controls. Standard head
pressure controls regulate the 100 and 50/50% condenser
capacity applications. Head pressure can also be controlled
by fan cycling controls supplemented by the accessory
Motormaster® V solid-state head pressure control. See Motor-
master V installation instructions for more information.
In the standard control scheme, fans 1 and 2 are on when
there is a call for cooling from the respective coil circuits. Fans
1 and 2 are non-cycling. On 054 and 064 units, fans 3 and 4 are
controlled by using a fan cycling pressure switch on each of the
primary coil circuits in response to condensing pressure. Fan
cycling switches must be replaced with the switches supplied
in the control box of the 30HXA chiller.
The fan cycling pressure switch controls the fans as follows:
Fans 3 and 4 are on above 185
±
10 psig (1276
±
69 kPa) and
off below 97
±
10 psig (669
±
69 kPa). If pressure is rising be-
tween 97 psig (669 kPa) and 185 psig (1276 kPa), fans 3 and 4
are off. If pressure is falling from 185 psig (1276 kPa) to
97 psig (669 kPa) fans 3 and 4 are on.
30GXN,R UNIT SIZE
FAN TYPE
NAVIGATOR OUTPUT
POINT NAME
FAN CONTACTOR
FANS CONTROLLED
253, 268
Standard
Comp. B1 contactor*
FC-1
1
Fan 1
FC-2
2,4
Fan 2
FC-3
3
Fan 4
FC-4
5,7
Fan 3
FC-5
6,8
Comp. A1/A2 contactor*
FC-6
9,10
Fan 3
FC-7
11,12
Fan 3
FC-8
13,14
Fan 1
FC-9
15,16
High Static
Comp. B1 contactor*
FC-1
1
Fan 1
FC-2, 2A
2,4
Fan 2
FC-3
3
Fan 4
FC-4, 4A
5,7
Fan 3
FC-5, 5A
6,8
Comp. A1/A2 contactor*
FC-6, 6A
9,10
Fan 3
FC-7, 7A
11,12
Fan 3
FC-8, 8A
13,14
Fan 1
FC-9, 9A
15,16
281-350
Standard
Comp. B1/B2 contactor*
FC-1
1,2
Fan 2
FC-2
3,4
Fan 4
FC-3
5,6
Fan 4
FC-4
7,8
Fan 1
FC-5
9,10
Comp. A1/A2 contactor*
FC-6
11,12
Fan 3
FC-7
13,14
Fan 3
FC-8
15,16
High Static
Comp. B1/B2 contactor*
FC-1, 1A
1,2
Fan 2
FC-2, 2A
3,4
Fan 4
FC-3, 3A
5,6
Fan 4
FC-4, 4A
7,8
Fan 1
FC-5, 5A
9,10
Comp. A1/A2 contactor*
FC-6, 6A
11,12
Fan 3
FC-7, 7A
13,14
Fan 3
FC-8, 8A
15,16
Comp.
—
Compressor
FC
—
Fan Contactor
FAN
FAN SWITCH
TEMPERATURE
FAN 2
ON
Above 65
±
3 F (18.3
±
1.7 C)
Between 55 and 65 F (12.8 and 18.3 C)
and temperature falling
OFF
Below 55
±
3 F (12.8
±
1.7 C)
Between 55 and 65 F (12.8 and 18.3 C)
and temperature rising
FAN 3
ON
Above 80
±
3 F (26.7
±
1.7 C)
Between 70 and 80 F (21.1 and 26.7 C)
and temperature falling
OFF
Below 70
±
3 F (21.1
±
1.7 C)
Between 70 and 80 F (21.1 and 26.7 C)
and temperature rising
