Space Pak ESP-3642J-V - Checking ESP-J Blower Motor; Checking ESP-J Low Voltage Transformer; Checking External Static Pressure

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CHECKING ESP-J BLOWER MOTOR
1. With voltmeter, check for selected voltage at input
terminals, L1 to N for 115V, L1 to L2 for 230V. Meas-
ured voltage should be ± 10V of selected line volt-
age.
2. Refer to SYSTEM START-UP AND ADJUST-
MENTS section. Ensure that the operating speed
for the current operating mode is adjusted.
CHECK ESP-J LOW VOLTAGE TRANSFORMER
1. Verify that the unit is configured for the selected
line voltage connected to the input terminal strip,
120V or 230V. Refer to STEP: 7 Wiring the Unit.
2. Measure the input voltage, either 120V L1 to N, or
230V L1 to L2. Input voltage should be within
±10% of nominal value.
3. If no voltage or voltage outside this range, verify
building power supply.
4. If proper voltage is present at the input terminal
strip, check transformer secondary voltage for 22-
28V across the blue and yellow terminals at the
24VAC terminal strip.
5. If measured voltage is zero, or outside this range,
replace the transformer.
CHECK EXTERNAL STATIC PRESSURE
You can use a U-tube manometer to check the exter-
nal static pressure on the duct system.
1. Puncture a ¼" diameter hole in the plenum duct at
least 18" from the fan coil unit.
2. Insert the high-side manometer tube into the hole
so that the end is approximately flush with the in-
side wall of the plenum, and perpendicular to the
direction of airflow.
3. System static pressure should be between 1.2" and
1.3" WC.
a. If the pressure is higher than 1.2" provide addi-
tional supply runs to increase airflow or lower
the fan speed by turning the fan speed adjust-
ment for the current mode of operation counter-
clockwise to reduce the static pressure.
b. If the pressure is lower than 1.2", look for leaks
in the supply plenum, restrictions in the return
system (including clogged filters) If more than
the recommended number of supply runs are in-
stalled, you may install flow restrictors (orifices)
in these runs. If the number of runs is appropri-
ate for the load, increase the static pressure by
turning fan speed adjustment for the current
mode of operation clockwise to increase the
static pressure.