551b ,c, Dc b a – Bryant 551C User Manual
Page 29
29
LED ON
LED ON
LED ON
LED ON
LED OFF
19
18
LED OFF
LED OFF
LED OFF
17
16
15
14
13
12
11
10
9
40
45
50
55
60
65
70
75
80
85
90
95 100
DEGREES FAHRENHEIT
mA
D
C
B
A
C06035
Fig. 34
--- Outside Air Temperature
Changeover Set Points
ECONOMI$ER IV
ECONOMI$ER IV
CONTROLLER
GROMMET
RETURN AIR
SENSOR
RETURN DUCT
(FIELD-PROVIDED)
C06036
Fig. 35
--- Return Air Temperature or Enthalpy
Sensor Mounting Location
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
1
4
1
6
18
20
2
2
24
26
28
30
32
3
4
36
38
40
42
44
46
9
0
1
0
0
80
70
6
0
50
40
30
20
10
ENTHALPY BTU PER POUND DRY AIR
85
(29)
90
(32)
95
(35)
100
(38)
105
(41)
110
(43)
35
(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
RELATIVE HUMIDITY (%)
HIGH LIMIT
CURVE
APPROXIMATE DRY BULB TEMPERATURE--degrees F (degrees C)
C06037
Fig. 36
--- Enthalpy Changeover Set Points
Occupancy Control
The factory default configuration for the EconoMi$er IV control
is occupied mode. Occupied mode is provided by the black
jumper from terminal TR to terminal N. When unoccupied mode
is desired, install a field-supplied timeclock function in place of
the jumper between TR and N. (See Fig. 27.) When the timeclock
contacts are closed, the EconoMi$er IV control will be in
occupied mode. When the timeclock contacts are open (removing
the 24-v signal from terminal N), the EconoMi$er IV will be in
unoccupied mode.
Demand Controlled Ventilation (DCV)
When using the EconoMi$er IV for demand controlled
ventilation, there are some equipment selection criteria which
should be considered. When selecting the heat capacity and cool
capacity of the equipment, the maximum ventilation rate must be
evaluated for design conditions. The maximum damper position
must be calculated to provide the desired fresh air.
Typically the maximum ventilation rate will be about 5 to 10%
more than the typical cfm required per person, using normal
outside air design criteria.
551B
,C