Nailor 37S Manual page 19

CONTROLLER/ACTUATOR
DAMPER
CW TO
CLOSE
BALANCING
TEES
16 I
V N
DC
24" (610)
LENGTH
1/4" (6) O. D.
TUBING TO
DIAMOND
FLOW
SENSOR
FACTORY
WIRING/PIPING
FIELD WIRING
CONTROL SEQUENCE A2 • COOLING WITH MORNING WARM-UP
(CONTINUOUS OPERATION)
Sequence of Operation:
Fan runs continuously, providing constant volume to the space. With room temperature at set
point, unit delivers minimum cooling airflow and maximum induced plenum air. On a rise in
room temperature, the thermostat regulates the controller/actuator to increase primary airflow.
As more cold air is supplied to the fan section, less warm air is induced from the ceiling plenum.
When the room temperature exceeds the setpoint by 2°F (1.1°C) or more, primary
airflow is maintained at the maximum setting. The maximum setting is usually the same
as the total fan volume setting.
On a decrease in room temperature, the thermostat regulates the controller/actuator to
decrease the airflow and as less cold air is supplied to the fan section, more warm air is
induced from the ceiling plenum. If room temperature continues to drop, minimum
primary airflow is maintained.
Primary airflow is held constant in accordance with thermostat demand. Any changes in
duct air velocity due to static pressure fluctuations are sensed and compensated for,
resulting in pressure independent control.
Minimum and maximum primary airflow limits are adjusted underneath the thermostat cover.
Morning Warm-up Cycle.
A duct mounted sensor is used to measure primary air temperature. Upon sensing a
central system supply air temperature above 77°F +/– 4 (25°C +/– 2.2), the primary air
damper will drive fully open regardless of flow limit settings. The terminal fan must be
energized. Central warm air is delivered to the space.
Note:
Constant volume series terminal fans should be interlocked to be energized ahead of or
when the central system fan starts, to prevent backflow of primary air into the ceiling
plenum and to prevent possible backward rotation of the terminal fan.
Options:
❑
Thermostat Scale Plate:
(Thermostat includes backing plate for 2" x 4" electrical box).
SCHEDULE TYPE:
PROJECT:
ENGINEER:
CONTRACTOR:
Nailor Industries Inc. reserves the right to change any information concerning product or pricing without notice.
ANALOG ELECTRONIC CONTROL
FAN POWERED TERMINAL UNIT • SERIES FLOW
CONSTANT VOLUME • PRESSURE INDEPENDENT
MODELS: 35S, 35SST, 37S AND 37SST A2
CSP-5002
V
N M M
N
O A I
O
O – –
R X N M
U 24V
M
A
METER
T AC
X
%
RED-CLS
M
GRN-OPN
I
N
C
LED
L
CCW CW O
S
E
STE-1002
DUCT TEMP. SENSOR
❑
°F or °C
CTE-5101 ROOM THERMOSTAT (DA)
SINGLE TEMP. SET POINT
12
V1 T3 R1 T1 + V A –
TERMINAL
V1 T1 + –
BLOCK
GROUND
REE-1005 COOLING/HEATING
CHANGEOVER RELAY MODULE
OCCUPIED CYCLE (Central System On).
MINIMUM
COLD
- 2°F
(-1.1°C)
MORNING WARM-UP CYCLE
- 2°F
(-1.1°C)
DATE
8 - 6 - 08
LINE
VOLTAGE
N H
TOGGLE
DISCONNECT
SWITCH
(OPTIONAL)
SPEED
CONTROLLER
24 VAC
TRANSFORMER
FACTORY
CAPACITOR
INSTALLED
FAN
JUMPER
MOTOR
TOTAL AIRFLOW
MIXING
SETPOINT
ROOM TEMPERATURE INCREASE
(Central System On).
MAXIMUM FLOW WITH WARM-UP ACTIVATED
SETPOINT
ROOM TEMPERATURE INCREASE
B SERIES SUPERSEDES DRAWING NO.
3500 12 - 2 - 02
MAXIMUM
COOLING
HOT
+ 2°F
(+1.1°C)
+ 2°F
(+1.1°C)
35SCD-A2