Manual

12. Start-up Procedures
Electrical shock hazard.
Use extreme care during all of the following checks and pro-
cedures.
Make sure electric power is turned OFF as instructed in ap-
propriate steps.
Failure to follow this warning can result in property damage,
personal injury, and/or death.
Circulating Air Blower
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 registers, diffusers,
grilles, dampers, heaters and filters.
3.To your system ESP determined in Step 2, add 0.05 In. W.C. for a
wet coil.
4.From the system design, determine the desired cooling airflow 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 attached to the
evaporator access panel on the unit.) From the table, determine the
speed tap required to achieve the desired airflow.
6. See next section, Speed Taps, to set the blower motor speed termi-
nal block (speed taps) to the cooling speed determined in the pre-
vious steps.
Speed Taps
After determiningtherequired CFM andspeedtapdata fromthe tech data
sheet, follow the steps below to change speeds if necessary.
FIGURE i4 L Blower Speed Tap Settings
10 SEER 2 TON MED
10 SEER 21/2 TON MED
10 SEER 3 TON LOW
10 SEER 31/2 TON MED HI
10 SEER 4 TON LOW
10 SEER 5 TON HI
FIGURE 15 I Blower Motor Speed Taps
I
Blower Speed Tap Block
Yellow
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 attached to
the same speed tap required for cooling/heat pump operation. See FIG-
URE 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 FIGURE 15 and the appropriate unit wiring diagram included 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 auxiliary 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 prop-
er 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.
3. Inspect the inside of the unit to be sure that all wires are in place and
all tools, etc. are removed.
4. Replace all service access panels.
Check the unit's operation as outlined in the following instructions. If any
unusual sparking, odors or noises are encountered, shut OFF electric
power immediately. Recheck for wiring errors, or obstructions in or near
blower motors.
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