![background image](http://html.mh-extra.com/html/carrier/weathermaker-50kcq-a04-series/weathermaker-50kcq-a04-series_service-and-maintenance-instructions_2560323039.webp)
39
Fig. 60 — Outside Air Temperature Changeover
Set Points
Fig. 61 — Outdoor-Air Damper Leakage
Differential Dry Bulb Control
For differential dry bulb control, the standard outdoor dry bulb
sensor is used in conjunction with an additional accessory dry
bulb sensor (part number CRTEMPSN002A00). The accessory
sensor must be mounted in the return airstream. (See Fig. 62.)
Wiring is provided in the EconoMi$er IV wiring harness.
Fig. 62 — Return-Air Temperature or Enthalpy
Sensor Mounting Location
In this mode of operation, the outdoor-air temperature is com-
pared to the return-air temperature and the lower temperature
airstream is used for cooling. When using this mode of
changeover control, turn the enthalpy set point potentiometer
fully clockwise to the D setting. (See Fig. 59.)
Outdoor Enthalpy Changeover
For enthalpy control, accessory enthalpy sensor (part number
HH57AC078) is required. Replace the standard outdoor dry
bulb temperature sensor with the accessory enthalpy sensor in
the same mounting location. (See Fig. 62.) When the outdoor
air enthalpy rises above the outdoor enthalpy changeover set
point, the outdoor-air damper moves to its minimum position.
The outdoor enthalpy changeover set point is set with the out-
door enthalpy set point potentiometer on the EconoMi$er IV
controller. The set points are A, B, C, and D. (See Fig. 63.) The
factory-installed 620-ohm jumper must be in place across ter-
minals SR and SR+ on the EconoMi$er IV controller.
Fig. 63 — Enthalpy Changeover Set Points
Fig. 64 — EconoMi$er IV Control
Differential Enthalpy Control
For differential enthalpy control, the EconoMi$er IV controller
uses two enthalpy sensors (HH57AC078 and CRENT-
DIF004A00), one in the outside air and one in the return air
LED ON
LED ON
LED ON
LED ON
LED OFF
19
18
LED OFF
LED OFF
LED OFF
17
16
15
14
1
3
12
11
10
9
40
45
50
55
60
65
70
75
80
85
90
95
100
DEGREE
S
FAHRENHEIT
mA
D
C
B
A
0
5
10
15
20
25
3
0
0.1
3
0.20
0.22
0.25
0.
3
0
0.
3
5
0.40
0.45
0.50
S
TATIC PRE
SS
URE (in. wg)
FLOW
IN
CUBIC
FEET
PER
MINUTE
(cfm)
ECONOMI$ER IV
ECONOMI$ER IV
CONTROLLER
GROMMET
RETURN AIR
S
EN
S
OR
RETURN DUCT
CONTROL
CURVE
A
B
C
D
CONTROL POINT
APPROX.
deg. F (deg. C)
AT 50% RH
73 (23)
70 (21)
67 (19)
63 (17)
12
14
16
1
8
20
2
2
2
4
2
6
28
30
32
3
4
3
6
38
40
42
4
4
4
6
9
0
1
0
0
80
7
0
60
50
40
30
20
10
E
NTHALPY
BTU PER
POUN
D DRY
AI
R
85
(29)
90
(32)
95
(35)
100
(38)
105
(41)
110
(43)
3
5
(2)
35
(2)
40
(4)
40
(4)
105
(41)
110
(43)
45
(7)
45
(7)
50
(10)
50
(10)
55
(13)
55
(13)
60
(16)
60
(16)
65
(18)
65
(18)
70
(21)
70
(21)
75
(24)
75
(24)
80
(27)
80
(27)
85
(29)
90
(32)
95
(35)
100
(38)
A
A
B
B
C
C
D
D
RELA
TI
VE HUMI
DI
TY (%
)
HIGH LIMIT
CURVE
TR1
24 V
a
c
COM
TR
24
V
a
c
HOT
1
2
3
4
5
EF
EF1
+
_
P1
T1
P
T
N
EXH
2V
10V
EXH
S
et
S
et
2V
10V
2V
10V
DCV
DCV
Free
Cool
B
C
A
D
S
O+
S
R+
S
R
S
O
AQ1
AQ
DCV
Min
Po
s
Open
M
a
x
N1
Summary of Contents for WeatherMaker 50KCQ A04 Series
Page 34: ...34 Fig 53 RTU Open Overlay for Economizer Wiring ...
Page 35: ...35 Fig 54 VFD Overlay for W2770 Controller Wiring ...
Page 70: ...70 Fig C 50KCQ A04 A05 A06 Control Wiring Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 71: ...71 Fig D 50KCQ A04 A05 A06 Power Wiring Diagram 208 230 1 60 APPENDIX D WIRING DIAGRAMS ...
Page 72: ...72 Fig E 50KCQ A04 A05 A06 Power Wiring Diagram 208 230 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 73: ...73 Fig F 50KCQ A04 A05 A06 Power Wiring Diagram 460 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 74: ...74 Fig G 50KCQ A04 A05 A06 Power Wiring Diagram 575 3 60 APPENDIX D WIRING DIAGRAMS ...
Page 75: ...75 Fig H 50KCQ Premier Link Control Diagram APPENDIX D WIRING DIAGRAMS ...
Page 76: ...76 Fig I 50KCQ RTU Open Control Diagram APPENDIX D WIRING DIAGRAMS ...