Carrier 19EF Series, Start Up & Operation Manual

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Safety Shutdown —
A safety shutdown is identical to
a manual shutdown with the exception that the LID will dis-
play the reason for the shutdown, the alarm light will blink
continuously, and the spare alarm contacts will be ener-
gized. A safety shutdown requires that the RESET softkey
be pressed in order to clear the alarm. If the alarm is still
present, the alarm light will continue to blink. Once the alarm
is cleared, the operator must press the
CCN or
LOCAL softkeys to restart the machine. Soft stop unload-
ing does not occur during safety shutdowns.
Do not reset starter loads or any other starter safety for
30 seconds after the compressor has stopped. Voltage
output to the compressor start signal is maintained for
10 seconds to determine starter fault.
BEFORE INITIAL START-UP
Job Data Required
• list of applicable design temperatures and pressures (prod-
uct data submittal)
• machine certified drawings
• starting equipment details and wiring diagrams
• diagrams and instructions for special controls or options
• 19EF Installation Instructions
• pumpout unit instructions
Equipment Required
• mechanic’s tools (refrigeration)
• digital volt-ohmmeter (DVM)
• clamp-on ammeter
• electronic leak detector
• absolute pressure manometer or wet-bulb vacuum indica-
tor (Fig. 23)
• 500 v insulation tester (megohmmeter) for compressor mo-
tors with nameplate voltage of 600 v or less, or a
5000-v insulation tester for compressor motor rated above
600 v
Remove Shipping Packaging —
Remove any pack-
aging material from the control center, power panel, guide
vane actuator, motor and bearing temperature sensor covers,
and the starter.
Open Oil Circuit Valves —
Check that the oil filter
isolation valves (Fig. 4) are open by removing the valve cap
and checking the valve stem.
Torque All Gasketed Joints —
Gaskets normally have
relaxed by the time the machine arrives at the jobsite. Tighten
all gasketed joints to ensure a leak tight machine.
Check Machine Tightness —
Figure 24 outlines the
proper sequence and procedures for leak testing.
19EF chillers are shipped with the refrigerant contained
in the condenser shell and the oil charge shipped in the com-
pressor. The cooler will have a 15 psig (103 kPa) refrigerant
charge. Units may be ordered with the refrigerant shipped
separately, along with a 15 psig (103 kPa) nitrogen-holding
charge in each vessel. To determine if there are any leaks,
the machine should be charged with refrigerant. Use an elec-
tronic leak detector to check all flanges and solder joints af-
ter the machine is pressurized. If any leaks are detected, fol-
low 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 —
Carrier recommends the use of
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.
Leak Test Machine —
Due to regulations regarding re-
frigerant emissions and the difficulties associated with sepa-
rating contaminants from refrigerant, Carrier recommends
the following leak test procedures. See Fig. 24 for an outline
of the leak test procedures. See Table 5A and 5B for refrig-
erant pressure/temperature values.
1. If the pressure readings are normal for machine
condition:
a. Evacuate the holding charge from the vessels, if present.
b. Raise the machine pressure, if necessary, by adding
refrigerant until pressure is at equivalent saturated pres-
sure for the surrounding temperature.
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.
Fig. 23 — Typical Wet-Bulb Type
Vacuum Indicator
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