Controls Start-Up, Operation, Service, and ... - Climayoreo

HPS
LEGEND
RRS
HPS — High-Pressure Switch
RRS — Reverse Rotation Switch (HK01CB002)
Fig. 32 — Reverse Rotation Switch Wiring
24. Locate the appropriate compressor item (‘CC.A1’, etc.)
under the COMP sub-mode and start the compressor.
Press ENTER , followed by to change the value to On,
and then ENTER again. Once the compressor has success-
fully started, energize both loaders one at a time. Let the
circuit stabilize with both loaders energized. Refer to the
Refrigerant Charging/Adding Charge and Oil Charging/
Low Oil Recharging sections of this document for
recharging procedures and performance criteria.
25. Once proper rotation has been verified, disconnect and
lock out the power to the chiller. The reverse rotation low
pressure switch can now be removed from the compressor
and high pressure switch circuit.
BURNOUT CLEAN-UP PROCEDURE — If a screw compressor
motor burns out on a 30GX,HX chiller, a simple cleanup
should be performed. The following procedure provides the
minimum steps to be taken before restarting the circuit.
1. Remove the oil from the oil separator. This can be facilitated
by connecting a hose to the port located on the
service valve entering the external oil filter. Run the hose
to a container(s) that can hold up to 5 to 6 gallons (19 to
20 L) of oil. Pressurize the circuit to force out most of the
oil in the separator. To remove the remaining oil, the
pre-lube pump can be run in the Service Test mode from
the Navigator. Enable the desired pump (either item
‘OL.P.A’ or ‘OL.P.B’ in the OUTS sub-mode). To prevent
wear to the pump components, do not allow the prelube
pump to operate “dry.”
2. Remove the failed compressor following the Compressor
Changeout Sequence procedure on page 57.
3. Once the compressor is removed access the oil catch pan
through the cooler-compressor mounting flange. Clean
out any debris which may have collected in the oil catch
pan.
4. Install a new compressor.
5. To dilute and remove any residual oil left in the separator,
pump approximately 1 /2 gallon (2 L) of compressor oil
into the oil separator using the Schrader port located on
top of the separator (30GXN,R) or on the discharge line
(30HXA,HXC) and remove using the pre-lube pump
describedinStep1.
6. Disconnect the hose from the external oil filter service
valve.
7. Install a new filter drier core and compressor external oil
filter. If desired, a burnout (activated carbon) core may be
used, but should be replaced with a standard filter drier
core during the next filter replacement.
8. Measure in the amount of Castrol SW 220 Polyolester oil
as specified on the nameplate of the chiller.
9. Leak check, evacuate and recharge the machine as
described in this manual with the amount of R-134a
stated on the chiller nameplate.
10. Perform periodic acid checks on the circuit and change
the filter drier core in the liquid line as necessary. Use the
Carrier Standard Service Techniques Manual as a source
of reference.
59
Moisture-Liquid Indicator — Clear flow of liquid
refrigerant indicates sufficient charge in the system. Note,
however, that bubbles in the sight glass do not necessarily indicate
insufficient charge. Moisture in the system is measured in
parts per million (ppm), changes of color of indicator are:
Green — moisture is below 80 ppm;
Yellow-green (chartreuse) — 80 to 225 ppm (caution);
Yellow (wet) — above 225 ppm.
Change filter drier at the first sign of moisture in the system.
IMPORTANT: Unit must in operation for at least
12 hours before moisture indicator can give an accurate
reading. With the unit running, the indicating element
must be in contact with liquid refrigerant to give true
reading.
Filter Drier — Whenever moisture-liquid indicator shows
presence of moisture, replace filter drier core. Refer to Carrier
Standards Service Technique Manual, Chapter 1, Refrigerants,
for details on servicing filter driers. Cleanable strainers have
been installed in each circuit’s liquid line to aid in removal of
system contaminants and debris.There is one industry standard
drier core in each strainer. See Fig. 33.
Liquid Line Service Valve — This valve is located
ahead of the filter drier and provides a 1 /4-in. Schrader connection
(30GXN,R only) for field charging. In combination with
compressor discharge service valve, each circuit can be
pumped down into the high side for servicing.
Thermistors — To aid in verifying thermistor performance,
resistances at various temperatures are listed for all
thermistors (except motor thermistors) in Tables 38A-39B. See
Table 40 for motor thermistor values.
LOCATION — General location of thermistor sensors and
terminal connections in the control box are listed in Table 3.
THERMISTOR REPLACEMENT
All thermistors are installed in wells and will slide out of
the wells easily. The wells are under refrigerant pressure
(cooler EWT and LWT are under waterside pressure) and
do not need to be removed to replace a faulty thermistor.
To Replace Thermistors T1, T2, T3, T4, T5, or T6 (Entering,
Leaving Water; Discharge Gas Temperature) — Disconnect
appropriate connector from the Main Base Board
(MBB) or Screw Compressor Board (SCB). Thermistors T1
and T2 are connected to MBB-J8 and thermistors T3 through
T6 are connected to EXV-J5. These six thermistors use insulation
displacement connectors. New thermistors should be
spliced to existing wiring close to the connector unless new
connectors are required. A special AMP crimping tool, part no.
58580-1, is needed if new connectors are used. Remove
thermistor cable from harness. Remove and discard original
thermistor from well. Insert new thermistor in well body to its
full depth. Add a small amount of thermal conductive grease to
thermistor probe and well. Thermistors are friction-fit
thermistors and will slip back into well located at the cooler
head (T1, T2) or at the top of each compressor discharge line
(T3 through T6). Secure thermistor to well body with a wire tie
to prevent thermistor from working its way out of the well. See
Fig. 34.