Evaporator Fan Performance Adjustment; Belt Tension Adjustment; Compressor Oil; Troubleshooting - Carrier Omnizone 50BV020-064 Installation, Start-Up, Service And Controls Operation And Troubleshooting

Sheave Alignment
1. To check the location of the fixed sheaves on the shafts, use a
straightedge or a piece of string. If the sheaves are properly
aligned, the string will touch them at the points indicated by
the arrows in Fig. 42. Rotate each sheave a half revolution to
determine whether the sheave is wobbly or the drive shaft is
bent. Correct any misalignment.
2. With sheaves aligned, tighten cap screws evenly and
progressively.
NOTE: There should be a 1/8 in. to 1/4 in. gap between the
mating part hub and the bushing flange. If the gap is closed,
the bushing is probably the wrong size.
3. With taper-lock bushed hubs, be sure the bushing bolts are
tightened evenly to prevent side-to-side pulley wobble.
Check by rotating sheaves and rechecking sheave alignment.
When substituting field-supplied sheaves for factory-supplied
sheaves, only the motor sheave should be changed.
String
Fixed Sheave
Fig. 42 — Sheave Alignment

Evaporator Fan Performance Adjustment

To change fan speeds from factory settings:
1. Shut off unit power supply.
2. Loosen nuts on the 4 carriage bolts in the mounting base.
Using adjusting bolts and plate, slide the motor and remove
the belt.
3. Loosen movable-pulley flange setscrew.
4. Screw the movable flange toward the fixed flange to increase
speed, and away from the fixed flange to decrease speed.
Increasing the fan speed increases the load on the motor. Do
not exceed the maximum speed specified in Tables 2 and 3.
5. Set the movable flange at nearest keyway of the pulley hub
and tighten the setscrew. (See Tables 2 and 3 for speed
change for each full turn of pulley flange.)
6. Replace and tighten the belts (see Belt Tension Adjustment
section).
7. Restore power to the unit.
Straight
Edge
To align fan and motor pulleys:
1. Loosen fan pulley setscrews.
2. Slide fan pulley along fan shaft.
3. Make angular alignment by loosening motor from mounting
plate.
4. Restore power to unit.

BELT TENSION ADJUSTMENT

Using a gauge, apply 4 lb of force to the center of the belt and ad-
just the tension until a deflection of 1/64 in. is achieved for every
inch of shaft center distance. See Fig. 43.
Ideal belt tension is the lowest value under which belt slip will not
occur at peak load conditions.
Fig. 43 — Fan Belt Tension

Compressor Oil

All units are factory charged with oil. It is not necessary to add oil
unless compressor(s) is removed from the unit. If necessary, oil
can be removed/charged via Schrader fitting. Operate the system
at high evaporator temperature prior to oil recharge to assist oil re-
turn to the compressor(s) from other system components. If neces-
sary, recharge the system as shown in Table 21.
Table 21 — Oil Recharge
50BV UNIT SIZE COMPRESSOR
020 ZP94KCE
024 ZP103KCE
J
028 ZP137KCE
034 ZP182KCE
034 ZP182KCE
044 ZP120KCE
T, V, W
054 ZP137KCE
064 ZP182KCE

TROUBLESHOOTING

Refer to Tables 22 and 23 to determine the possible cause of the
problem and the associated procedure necessary to correct it.
Table 22 — CV Units LED Diagnostic Codes
NO. OF BLINKS
1
2
3
4
5
6
NOTE(S):
a. The main control board has a red LED (light-emitting diode) for fault indication
and will blink a code as described above. Count the number of blinks to deter-
mine the lockout condition.
b. Freeze protection and condensate overflow lockout require optional sensors.
55
LB Force
Deflectio n
OIL CHARGE (oz)
81
106
106
106
3MA-POE
106
106
106
106
DESCRIPTION
1st Stage High-Pressure Lockout
1st Stage Low-Pressure Lockout
2nd Stage High-Pressure Lockout
2nd Stage Low-Pressure Lockout
Freeze Protection Lockout
b
Condensate Overflow Lockout
OIL
TYPE
a
b