Open-Drive Motor Auxiliary Devices; Open Oil Circuit Valves; Tighten All Gasketed Joints And Guide Vane Shaft Packing; Check Machine Tightness - Carrier 17 Start Up & Operation Manual

Open-Drive Motor Auxiliary Devices —
iary devices such as resistance temperature detectors, ther-
mocouples, thermoguards, etc., will generally terminate on
terminal blocks located in the auxiliary terminal box on the
motor. Other devices may terminate on their own enclosures
elsewhere on the motor. Such information can be obtained
by referring to the certified drawing. Information regarding
terminal designation and the connection of auxiliary devices
can be obtained from auxiliary drawings referenced by the
outline drawing.
If the motor is provided with internal space heaters, the
incoming voltage supplied to them must be exactly as shown
by either a nameplate on the motor or the outline drawing
for proper heater operation. Caution must be exercised any-
time contact is made with the incoming space heater circuit
as space heater voltage is often automatically applied when
the motor is shut down.
Open Oil Circuit Valves —
isolation valves are open by removing the valve cap and check-
ing the valve stem. (See Scheduled Maintenance, Changing
Oil Filter, page 76.)
Tighten All Gasketed Joints and Guide Vane
Shaft Packing —
Gaskets and packings normally relax
by the time the machine arrives at the jobsite. Tighten all
gasketed joints and the guide vane shaft packing to ensure a
leak-tight machine.
NOTE: On open-drive machines, check the machine cold align-
ment. Refer to Machine Alignment in the Maintenance
section.
Check Machine Tightness —
proper sequence and procedures for leak testing.
17/19EX chillers may be shipped with the refrigerant con-
tained in the utility vessel and the oil charge shipped in the
compressor. The cooler/condenser vessels will have a 15 psig
(103 kPa) refrigerant charge. Units may also be ordered with
the refrigerant shipped separately, along with a 15 psig
(103 kPa) nitrogen-holding charge in each vessel. To deter-
mine if there are any leaks, the machine should be charged
with refrigerant. Use an electronic leak detector to check all
flanges and solder joints after the machine is pressurized. If
any leaks are detected, follow the leak test procedure.
If the machine is spring isolated, keep all springs blocked
in both directions in order to prevent possible piping stress
and damage during the transfer of refrigerant from vessel to
vessel during the leak test process, or any time refrigerant is
transferred. Adjust the springs when the refrigerant is in op-
erating condition, and when the water circuits are full.
Refrigerant Tracer —
an environmentally acceptable refrigerant tracer for leak test-
ing with an electronic detector or halide torch.
Ultrasonic leak detectors also can be used if the machine
is under pressure.
Do not use air or oxygen as a means of pressurizing the
machine. Some mixtures of HFC-134a and air can un-
dergo combustion.
Auxil-
Check that the oil filter
Figure 28 outlines the
Carrier recommends the use of
Leak Test Machine —
frigerant emissions and the difficulties associated with sepa-
rating contaminants from refrigerant, Carrier recommends
the following leak test procedures. See Fig. 28 for an outline
of the leak test procedures. Refer to Tables 5A and 5B for
refrigerant pressure/temperature values and to Pumpout and
Refrigerant Transfer Procedures section, page 64.
1. If the pressure readings are normal for machine
condition:
a. Evacuate the nitrogen holding charge from the ves-
sels, if present.
b. Raise the machine pressure, if necessary, by adding
refrigerant until pressure is at equivalent saturated pres-
sure for the surrounding temperature. Follow the
pumpout procedures in the Pumpout and Refrigerant
Transfer Procedures section, page 64.
Never charge liquid refrigerant into the machine if the
pressure in the machine is less than 35 psig (241 kPa).
Charge as a gas only, with the cooler and condenser pumps
running, until this pressure is reached, using PUMP-
DOWN LOCKOUT and TERMINATE LOCKOUT mode
on the PIC. Flashing of liquid refrigerant at low pres-
sures can cause tube freezeup and considerable
damage.
c. Leak test machine as outlined in Steps 3 - 9.
2. If the pressure readings are abnormal for machine
condition:
a. Prepare to leak test machines shipped with refrigerant
(Step 2h).
b. Check for large leaks by connecting a nitrogen bottle
and raising the pressure to 30 psig (207 kPa). Soap
test all joints. If the test pressure holds for 30 minutes,
prepare the test for small leaks (Steps 2g - h).
c. Plainly mark any leaks which are found.
d. Release the pressure in the system.
e. Repair all leaks.
f. Retest the joints that were repaired.
g. After successfully completing the test for large leaks,
remove as much nitrogen, air, and moisture as pos-
sible, given the fact that small leaks may be present in
the system. This can be accomplished by following
the dehydration procedure, outlined in the Machine De-
hydration section, page 51.
h. Slowly raise the system pressure to the equivalent satu-
rated pressure for the surrounding temperature but no
less than 35 psig (241 kPa) by adding HFC-134a
refrigerant. Proceed with the test for small leaks
(Steps 3-9).
3. Check the machine carefully with an electronic leak de-
tector, halide torch, or soap bubble solution.
4. Leak Determination — If an electronic leak detector in-
dicates a leak, use a soap bubble solution, if possible, to
confirm. Total all leak rates for the entire machine. Leak-
age at rates greater than 1 lb/year (0.45 kg/year) for the
entire machine must be repaired. Note total machine leak
rate on the start-up report. This leak rate repair is only for
new start-ups. See page 67 for operating machine leak
rate/repair recommendations.
48
Due to regulations regarding re-