13
START-UP
Complete Unit Start-Up Checklist on page CL-1 during ini-
tial start-up of this system.
System Evacuation and Dehydration —
Refer to
GTAC II, Module 4, ‘‘Dehydration for Proper Evacuation and
Dehydration Techniques.’’
Charging Procedure — (Units Matched with
30HX Chillers)
1. An initial refrigerant charge must be added after evacua-
tion to allow the unit to start. Add approximately 2 lb/
nominal ton (0.26 kg/nominal kW) liquid refrigerant
charge to the condenser. This amount of charge should be
sufficient to allow the unit to start. The approximate sys-
tem charges are shown in the installation manual for the
30HX chillers.
2. Raise the compressor discharge to approximately 125 F
(51.7 C) saturated discharge temperature (185 psig
[1276 kPa]) by throttling the condenser air (or water) in-
take.
3. Add liquid charge into the cooler until there is approxi-
mately 18 to 20 F (10.0 to 11.1 C) of system subcooling
(saturated discharge temperature — actual temperature
entering the electronic expansion device [EXD]). When
adding charge, use the
1
/
4
-in. Schrader-type fitting locat-
ed on the tube going into the bottom of the cooler. This
fitting is located between the EXD and the cooler. When
adding charge during unit operation, always use this port
so that the cooler liquid level sensor can detect the addi-
tional charge and adjust the EXD valve position.
NOTE: Electronic Expansion Device (EXD) refers to
EXV (Electronic Expansion Valve) (30HX076-146 units)
or Economizer (30HX161-271 units).
4. Check for a clear sight glass. If the unit is not fully load-
ed, the sight glass may be flashing. This condition is nor-
mal for a partially loaded unit. If the unit is fully loaded
and the sight glass is flashing, check EXV valve position.
If it is greater than 60% add additional charge.
SERVICE
Fan Guard Removal —
Remove the eight
1
/
4
- x
5
/
8
-in.
self-tapping hex-head screws that hold the fan grille to the
condenser-fan panel, and remove the grille.
Condenser Fan Adjustment
1. Be sure power is off to the condenser-fan motor.
2. Remove the fan guard.
3. Remove the cap, and set screws on the fan hub.
4. Adjust fan. See Fig. 10.
5. Tighten fan hub securely on the motor shaft with set
screw that bears against the key.
6. Replace the permagum sealing material and the rubber
cap over the end of the motor shaft to prevent moisture
from causing fan to rust on the shaft.
7. Replace the fan guard.
Fan Motor Removal
1. Make certain condenser power is off.
2. Remove fan guard and fan.
3. Loosen nut on the motor holding clamp that secures mo-
tor to motor support.
4. Lift motor upward. Remove the fan wheel through the fan
discharge opening. Remove wire connectors.
5. Replace in opposite order. Be sure to check location of
fan in orifice when replacing fan.
MAINTENANCE
Cleaning —
The 09AZ units should be thoroughly cleaned
inside and out. Frequency of cleaning depends on unit location
and area conditions.
Cleaning Condenser Coils —
Clean coils with a vac-
uum cleaner, fresh water, compressed air, or a bristle brush (not
wire).
The 09AZ units require very little maintenance. Regular
maintenance should include cleaning the surface of the coil and
checking to make sure that all electrical connections are tight.
All motors have permanently sealed ball bearings that do not
require lubrication. Check for loose electrical connections, oil
level, proper refrigerant charge, and refrigerant piping leaks.
Backflush coil to remove debris. Commercial coil cleaners
may also be used to help remove grease and dirt. Steam clean-
ing is NOT recommended. Wash coil in the opposite direction
of airflow. Units installed in corrosive environments should
be cleaned as part of a planned maintenance schedule. In this
type of application, all accumulations of dirt should be cleaned
off the coil. Condenser-fan motors are drip-proof but not
watertight.
Lubrication —
Fan motors have permanently lubricated
ball bearings; no additional lubrication is required.
TROUBLESHOOTING
See Table 5 for problems and possible solutions.
To prevent personal injury, be sure wire fan guards are
secured in place over each fan discharge (or that fans are
ducted), before starting the unit.
To prevent personal injury, be sure wire fan guards are
secured in place over each fan discharge before starting the
unit.
Do not use high-pressure water or air to clean condenser
coils. Damage to fins may result.
FILL HOLE IN FAN HUB
WITH PERMAGUM
FAN BLADE
HUB PLATE
HUB
FAN SHAFT
TOP
COVER
1/3 HEIGHT OF FAN
BLADE ABOVE VENTURI LIP
Fig. 10 — Location of Propeller on Motor Shaft
from Outside of Orifice Ring
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