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Start - Up
Start - Up
Perform the following steps prior to
starting the unit.
1. Inspect electrical connections. They
should be clean and secure.
Compare actual wiring with specific
diagrams provided on the unit.
2. Check piping and valves for leaks.
Open or close the valves to check
for proper operation. Drain lines
should be open.
CAUTION
The use of untreated or improperly
treated water in unit coils may
cause scaling, erosion, corrosion,
algae, smile or other equipment
damage. Consult a qualified water
treatment specialist to determine if
water treatment is required. The
Trane Company assumes no
respon-sibility for equipment
damage caused by untreated or
improperly treated water.
3. If equipped with a refrigerant coil,
charge and leak-test the unit and
get it ready for operation according
to instructions provided with the
condenser equipment.
4. Check that all air filters are in place
and positioned properly. Under
Periodic Maintenance, see section
titled “Air Filters.”
5. Close and secure all unit access
doors. Check that the latch set
screws are tight.
6. Remove all foreign material from the
drain pan and check drain opening
and condensate line for obstruc-
tions.
7. Prime the DRAIN TRAP.
Start-up Procedures
After completing all start-up checks
and procedures, the unit may be
started. The following checks and
adjustments should be made during
initial start-up:
WARNING
Disconnect electrical power prior
to access into a fan or ductwork.
Even when locked out electrically,
fans may cause injury or damage
if the impeller is subject to “wind-
milling.”The impeller should be
secured to physically restrict
rotational move-ment. Failure to
secure impeller can cause severe
personal injury r death. Disconnect
electrical power source when
connecting or disconnecting
electrical wires for test procedures.
Do not open service access doors
while the unit is operating. Failure
to exercise caution or while
inspecting. unit operation may
result in injury or death from
electrical shock, air movement or
rotating parts.
If the unit was stored for an extended
period of time, the following items
should be checked before starting the
unit.
1. Inspect motor bearings for moisture
and rust. Replace bearings if
necessary and repack with new
grease.
2. Check motor winding. An
acceptable winding resistance
reading is from 6 meg-ohms to
infinity. If reading is less than 5
Meg-ohms, winding should be
dried out in an oven or by ablower.
3. Inspect the entire motor for rust and
corrosion.
4. Lubricate the motor as instructed in
the section titled “Periodic
Maintenance,”or as indicated by
the maintenance tag on the motor.
5. Bump-start unit and observe the fan
wheel for proper rotation, as
indicated by rotation arrow located
on fan housing.
6. Measure the motor voltage and
ampeage on all phases to ensure
proper operation. The readings
Should fall within the range given
on the motor nameplate.
Maximum allowable voltage imbalance
is two percent. Voltage imbalance is
defined as 100 times the sum of the
deviation of the three voltage from the
average, divided by twice the average
voltage. For example, if the three
measured voltages are 221, 230 and
227, the average would be 226 volts.
The percent of voltage imbalance is
then calculated:
100 x {[226-221] + [230-226] + [227-226]}
2 x 226
= 2.2% (Unacceptable)
In this example, 2.2 percent imbalance
is not acceptable and the power
company should be notified to correct
it.
7. Check unit vibration if the fan speed
is changed more than 5% from the
original designed rpm, or if parts
such as shafts, fan wheels, bear-
ings, or other drive components are
replaced. Do not exceed max. fan
rpm.
8. Pay particular attention to any
vibration, noise or overheating of the
motor and fan bearings.
(Bearings may run warm during
break in.)
Determine Fan RPM
Fan rpm can be determined by using a
strobe-type tachometer, or revolution
counter.
Sheave Alignment
Align the fan and motor sheaves by
using a straightedge. The straightedge
must be long enough to span the
distance between the outside edges of
the sheaves. For more details refer to
maintenance section.
Excessive Vibration
EXCESSIVE VIBRATION MUST BE
CORRECTED TO PREVENT BEAR-
ING AND SHAFT DAMAGE. SEE THE
SECTION TITLED “TROUBLE-
SHOOTING”FOR DETAILS ON THE
COMMON CAUSES FOR VIBRATION.
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