Start-Up; Check List; Service; General - Carrier 39SH Installation, Start-Up And Service Instructions Manual

START-UP

Make a walkway inside unit components to
Check List —
protect insulation. Remove all construction debris from unit
interior. Remove walkway before starting unit.
FILTERS — Install unit filters in all filter sections.
FANS
1. Check lubrication of fan, motor bearings, and linkages.
a. Note that bearings are shipped completely full of
grease for corrosion protection and may run warm
temporarily on start-up until excess grease has
discharged.
b. Hand-operate all damper linkages to check for
freedom of movement.
2. Check tightness of bearing setscrews or locking collars.
Also, check tightness of setscrews on fan wheels and
sheaves.
3. Check tightness of fan shaft bearing mounting.
4. Recheck sheave alignment and belt tension. (Refer to
Fig. 49 and 50.)
5. Hand turn fan to make certain fan wheel does not rub in
housing.
6. Check fan speed with a strobe-type tachometer or use the
following formula: Obtain the motor rpm from the fan
motor nameplate and read sheave pitch diameters marked
on the fan and motor pulleys, or estimate the pitch diame-
ters by using the pulley outside diameters.
Then:
Motor Rpm x Motor Sheave
Pitch Diameter (in.)
Fan Rpm =
Fan Sheave Pitch Diameter (in.)
Example:
Nameplate Motor
Rpm =
Mtr Sheave Pitch
Diameter =
Fan Sheave Pitch
Diameter =
Fan Rpm =
=
=
Refer to the product data catalog for maximum allowable
fan speeds for standard wheels. Excessive fan speed may
result in condensate carryover from cooling coil or fan
motor overload and wheel failure.
7. Check direction of rotation (see Fig. 61). Arrow on drive
side of fan housing indicates correct direction of rotation.
a39-777.tif
Fig. 61 — Fan Wheel Rotation
Actual Approximate
1760 1760
8.9 in. 9.0 (OD)
12.4 in. 12.5 (OD)
1760 x 8.9 1760 x 9
12.4 12.5
1263 Rpm 1267 Rpm
8. Check vibration. If excessive vibration occurs, check for
the following:
a. Variable sheave (if air balance of system has been
accomplished: replace sheave with fixed sheave
for continuous application).
b. Drive misalignment.
c. Mismatched, worn or loose belts.
d. Wheel or sheaves loose on shaft.
e. Loose bearings.
f. Loose mounting bolts.
g. Motor out of balance.
h. Sheaves eccentric or out of balance.
i. Vibration isolators improperly adjusted.
j. Out-of-balance or corroded wheel (rebalance or
replace if necessary).
k. Accumulation of material on wheel (remove
excess material).

General

1. Place a suitable walkway to protect floor insulation
whenever entering the fan section.
2. Review Safety Considerations at beginning of these in-
structions. Good safety habits are important tools when
performing service procedures.
3. To make speed measurements, use a strobe-style tachom-
eter or calculate per Step 6 of Start-Up, Check List.

Fan Motor Replacement

1. Shut off motor power.
2. Disconnect and tag power wires at motor terminals.
3. Loosen motor brace-to-mounting-rail attaching bolts.
Loosen belt tensioning bolts to adjust the motor position
so V-belts can be removed without stretching over
grooves.
4. Mark belt as to position. Remove and set aside belts.
5. Remove motor to motor bracket holddown bolts.
6. Remove motor pulley and set aside.
7. Remove motor.
8. Install new motor. Reassemble by reversing Steps 1-6. Be
sure to reinstall multiple belts in their original position.
Use a complete new set if required. Do not stretch belts
over sheaves. Review the sections on motor and sheave
installation, sheave alignment and belt tensioning dis-
cussed previously (Fig. 48-50).
9. Reconnect motor leads and restore power. Check fan for
proper rotation as described in Start-Up, Check List.

Coil Cleaning

DETERGENT — Spray mild detergent solution on coils with
garden-type sprayer. Rinse with fresh water. Check to ensure
condensate line is free. Excess water from cleaning may flood
unit if condensate line is plugged.

Winter Shutdown (Chilled Water Coil Only)

ANTIFREEZE METHODS OF COIL PROTECTION

1. Close coil water supply and return valves.
2. Drain coil as follows:
Method I — 'Break' flange of coupling at each header
location. Separate flange or coupling connection to facili-
tate coil draining.
Method II — Open both valves to auxiliary drain piping.
34

SERVICE