KRUEGER KLPS - Field Adjustment of Airflow Set Points (Parallel); Field Adjustment of Minimum and Maximum Airflow Set Points

19
Fan Powered Terminal Units IOM
FIELD ADJUSTMENT OF MINIMUM AND MAXIMUM AIRFLOW
SET POINTS
Each parallel fan unit is equipped with a four quadrant
multi-point center averaging airow sensor that provides
an amplied dierential pressure that is proportional to
the unit airow. Output from this probe is used to provide a
ow signal to both pneumatic and electronic controls. Unit
airow (cfm) can be read directly from the ow probe on the
unit.
1. After the unit airow from the fan has been set, turn on
primary (VAV) air supply and turn o the fan.
2. To set cfm in the eld, connect a gage to the ow probe
and check the dierential pressure.
3. If a minimum VAV ow is required in heating mode, adjust
the volume controller until the dierential pressure
corresponds to the cfm required.
4. Some control sequences allow the fan to start before the
VAV damper reaches minimum setting, for an overlapping
of fan and VAV ow. For these sequences, after controller
min airow has been adjusted, the total airow with
both fan and primary airow should be checked. For
sequences that call for the fan to start as the rst stage
of heat, the cooling minimum cfm can be veried at the
diuser. Setting the minimum control point will typically
require careful adjustment of the thermostat to create a
minimum cooling demand signal.
a. Set the controller to provide maximum cooling
demand. This is typically accomplished by setting
the thermostat to the lowest possible temperature
setting. For most control sequences, this will cause
the fan to shut o.
b. Adjust the volume controller until the dierential
pressure (measured through the ow probe as
described above) corresponds to the cfm required.
6. Return all reheat options to normal connections.
7. Cap the ends of the inlet ow sensors.
8. Reset the thermostat to a normal setting.
5.
TABLE 11 - KQFP Parallel Fan Terminal Unit
UNIT SIZE INLET SIZE
PRIMARY AIR FLOW PCS MOTOR ECM MOTOR
MAX MIN MOTOR HP MAX FAN MIN FAN MOTOR HP MAX FAN MIN FAN
2
6 515 90
1/4 500 150 N/A
8 920 16
3
6 515 90
1/4 800 160 N/A8 920 160
10 1430 250
4
6 515 90
1/4 900 190 1/2 1000 250
8 920 160
10 1430 250
12 2060 360
5
10 1430 250
1/2 1700 480 N/A12 2060 360
14 2800 480
6
10 1430 250
1/2 1700 500 N/A
12 2060 360
14 2800 480
16 3660 630
7
10 1430 250
3/4 2000 780 1 1600 400
12 2060 360
14 2800 480
16 3660 630
TABLE 11 - KQFP Parallel Fan Terminal Unit