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d. Balance each outlet according to the requirements
calculated in previous steps.
8. Balance the unit fan discharge:
a. Measure the total flow discharging from the unit.
b. Adjust the discharge flow from the unit using the unit
electronic speed control (SCR).
9. Reconnect the damper actuator to the velocity controller
with the fan still running. Make sure the piping is as shown
on the unit piping/wiring diagram.
10. Balance the primary (cooling) air volumes:
NOTE: To balance the primary air side of the 45M,N,R
units only, the blower motor must be disconnected.
a. Connect a Magnehelic or inclined manometer (0 to
2.0 in. wg scale, maximum) to the differential pres-
sure sensor tubing.
b. Measure the volume of air flowing through the inlet
using the calibration curve affixed to the unit.
c. Adjust the “LO STAT” knob, with a 0 psi thermostat
signal, to obtain the desired airflow setting. Depend-
ing on the control sequence desired, the “LO STAT”
knob will vary either the minimum setting or the
maximum setting as follows:
DANC — “LO STAT” knob adjusts the minimum
setting.
RANC — “LO STAT” knob adjusts the maximum
setting.
DANO — “LO STAT” knob adjusts the minimum
setting.
RANO — “LO STAT” knob adjusts the maximum
setting.
Operation Sequences
1. During maximum thermostat cooling demand, the pri-
mary air damper will open in the maximum airflow setting
providing cold primary air at the preset maximum volume.
Accessory coils, if supplied, are off, and the unit should
discharge primary air only.
2. When the thermostat modulates between maximum cool-
ing and satisfied set point, the primary air damper responds
by proportional settings. Accessory coils, if supplied, are
off. The 45J,K,Q units only will be inducing plenum air
and mixing it with the cold primary air. The 45M,N,R fan
will not induce any plenum air at this point.
3. When the thermostat is modulating between maximum
heating demand and satisfied setpoint, the primary air
damper will be at the minimum air volume setting. A max-
imum amount of plenum air is induced at this point. In se-
quence, the first and second stages of electric reheat will
energize, if supplied. If hot water heating coils are supplied,
they will either open fully or modulate open.
4. During thermostat demand for maximum heating, primary
air will flow through the unit at the preset minimum set-
ting, maximum amount of plenum air will be induced, and
heating coils, if supplied, are full on. See Table 15 for
pneumatic control troubleshooting.
5. Adjust the “HI STAT” knob, with a 15 psi thermostat sig-
nal, to obtain the desired airflow setting. Depending on
the control sequence desired, the “HI STAT” knob will
vary either the minimum setting or the maximum setting
as follows:
DANC — “HI STAT” knob adjusts the maximum setting
RANC — “HI STAT” knob adjusts the minimum setting
DANO — “HI STAT” knob adjusts the maximum setting
RANO — “HI STAT” knob adjusts the minimum setting
6. To adjust the thermostat reset start point, remove gage port
(“G”) cap and attach a 0 to 30 psi pressure gage and note
the pressure reading. Adjust the thermostat pressure to the
controller, “T” port to the desired start point. Adjust the
“RESET START” knob until the gage pressure begins to
change slightly. Remove pressure gage and replace cap.
7. To adjust the thermostat reset span from standard 5 psi, re-
move gage port (“G”) cap and attach a 0 to 30 psi pressure
gage and note the pressure reading. Adjust the thermostat
pressure to the controller “T” port to the desired start point.
Adjust the “RESET SPAN” knob until the gage pressure
equals the desired reset span. Remove gage and replace
cap.
8. To change logic from a given sequence to another, follow
the steps below:
a. To change from N.O. to N.C. or from N.C. to N.O.,
loosen the “damper” dial screw and rotate the dial
until the desired damper position indicator is aligned
with the arrow. The VAV damper must be physically
changed to desired position.
b. To change from DA to RA or from RA to DA, no
configuration changes are required — use the appro-
priate calibration procedures from above.
9. Reconnect the power to the blower motor on the 45M,N
units.
NOTES:
1. The multi-function control system uses a KMC CSC 3000
series velocity controller with a rated air consumption of
1.00 SCFH at 20 psi main air pressure.
2. The maximum and minimum limits are both changed when
adjusting the center knob. The center knob should always
be set first.
Analog Controls Installation and Balancing
Procedures
The Analog Electronic Control System is a pressure indepen-
dent volume reset control that uses a KMC CSP-4702 controller-
actuator (see Fig. 17).
Adjustments for the minimum and maximum airflow settings
are made at the thermostat. The thermostat (CTE-5202) operates
on a 16 VDC power supply from the CSP 4702 controller and
outputs a 0 to 10 VDC signal on the AO1 and AO2 terminals.
AO1 is used as the cooling output and AO2 is used as the heating
output.