Manual
8. Start-up Procedures
Electrical shock hazard.
Use extreme care during all of the following checks
and procedures.
Make sure electric power is turned OFF as instructed
in appropriate steps.
Failure to follow this warning can result in property
damage, personal injury, and/or death.
Circulating Air Blower
Final Electrical Check
Make a final wiring check to be sure system is correctly wired. In-
spect field installed wiring and the routing to ensure that rubbing
or chafing due to vibration will not accur.
NOTE: Wiring Must be installed so it is protected from possible
mechanical damage.
CAUTION
Do NOT operate unit on cooling when the outdoor tempera-
ture is below 60°F. This is necessary to prevent possible
damage to the compressor.
Determining Blower Speed
1. Turn electric power OFF.
2. From the system design, determine the total external static
pressure (ESP) for the supply ducts, return ducts and regis-
ters, diffusers, grilles, dampers, heaters and filters.
3. To your system ESP determined in Step 2, add 0.05 In. W.C.
for a wet coi!.
4. From the system design, determine the desired cooling air-
flow in cubic feet per minute (CFM).
5. Locate the unit's Blower Performance Data table on the tech
data label for the unit's voltage. (The tech data sheet is at-
tached to the evaporator access panel on the unit.) From the
table, determine the speed tap required to achieve the de-
sired airflow.
6. See next section, Speed Taps, to set the blower motor
speed terminal block (speed taps) to the cooling speed deter-
mined in the previous steps.
Speed Taps
After determining the required CFM and speed tap data from the
tech data sheet, follow the steps below to change speeds if nec-
essary.
FIGURE i4 [ Blower Speed Tap Settings
10 SEER 3 TON LOW
10 SEER 4 TON LOW
10 SEER 5 TON HI
NOTE: The speed taps that the manufacturer sets from the facto-
ry for this product are based on a nominal 400 CFM per ton cool-
ing and the basic mid range on the temperature rise for heating.
Since the manufacturer cannot establish the static pressure that
will be applied to the unit, it is the responsibility of the installing
dealer / contractor to select the proper speed taps for the applica-
tion when the unit is installed.
FIGURE 15 I Blower Motor Speed Taps
L
Blower Speed Tap Block
Auxiliary Electric Heat B
Wire (if used)
connects here
BE SURE TO CHECK BLOWER MOTOR SPEED DATA ON THE
UNITS TECHNICAL DATA LABEL LOCATED ON THE UNIT.
NOTE: On Heat Pumps Electric heater blower wire must be at-
tached to the same speed tap required for cooling/heat pump op-
eration. See FIGURE 11 notes, The yellow lead MUST always
be connected to the speed tap block at the common quick connect
terminal. The terminal is identified as COM.
Refer to NO TAG and the appropriate unit wiring diagram in-
cluded in this manual. Wire the black wire to the required speed
tap terminal to achieve required airflow determined in Step 5.
Cooling, Heating (Heat Pump) and Auxiliary
Electric Strip Heat
NOTE: The cooling, heat pump and strip heat airflows are all on
the same speed tap. The refrigerant system requires the same
specific CFM for proper operation in the cooling and the heat
pump mode. For this reason, cooling and heating airflow must be
the same. DO NOT SPLIT OUT INTO A COOLING SPEED AND
HEATING SPEED. If auxiliary electric heat is installed, the auxil-
iary electric heat blower speed wire must be connected to the
black wire insulated quick connect terminal.
Check Before Starting
1. Check that the blower motor speed terminal block is set to
the proper cooling speed. Refer to the unit wiring diagram
and the various airflow tables in this manual.
2. Check to see that clean, properly sized field supplied air
filters are installed in the return air duct.
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