Hydronic Package; Replacement Modules; Pump Performance Check; Pump Modifications And Impeller Trimming - Carrier AQUASNAP 30RAP010-150 Controls, Start-Up, Operation, Service, And Troubleshooting

Air-cooled chillers with puron refrigerant (r-410a)
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WARNING
Electrical shock can cause personal injury and death. Shut
off all power to this equipment during installation. There
may be more than one disconnect switch. Tag all discon-
nect locations to alert others not to restore power until work
is completed.
1. Check that all power to unit is off. Carefully disconnect
all wires from the defective module by unplugging its
connectors.
2. Remove the defective module by removing its mounting
screws with a Phillips screwdriver, and removing the
module from the control box. Save the screws later use.
3. Verify that the instance jumper (MBB) or address switch-
es (all other modules) exactly match the settings of the
defective module.
NOTE: Handle boards by mounting standoffs only to
avoid electrostatic discharge.
4. Package the defective module in the carton of the new
module for return to Carrier.
5. Mount the new module in the unit's control box using a
Phillips screwdriver and the screws saved in Step 2. See
Table 34 for replacement module part numbers.
6. Reinstall all module connectors. For accessory Naviga-
tor™ display replacement, make sure the plug is installed
at TB3 in the LEN connector.
7. Carefully check all wiring connections before restoring
power.
8. Verify the ENABLE/OFF/REMOTE CONTACT switch
is in the OFF position.
9. Restore control power. Verify that all module red LEDs
blink in unison. Verify that all green LEDs are blinking
and that the scrolling marquee or Navigator display is
communicating correctly.
10. Verify all configuration information, settings, set points
and schedules. Return the ENABLE/OFF/REMOTE
CONTACT switch to its previous position.
Table 34 — Replacement Modules
REPLACEMENT
MODULE
PART NO. (with
Software)
Main Base
30RA502134
Board (MBB)
Scrolling
Marquee
HK50AA031
Display
Energy
Management
30GT515218
Module
(EMM)
Navigator
HK50AA033
Display
EXV
30GT515217
AUX
32GB500442E
CXB
30GT515219
Hydronic Package —
factory-installed hydronic package, consult the information be-
low for proper maintenance and service. In addition to this
information, each factory-installed hydronic package is sup-
plied with a packet of information supplied by the manufactur-
er, Bell & Gossett. Carrier Corporation strongly recommends
that this information be thoroughly reviewed prior to operation
of the chiller.
REPLACEMENT PART
NO. (without Software)
HK50AA029
HK50AA030
HK50AA028
N/A
HK50AA026
N/A
HK50AA027
If the unit is equipped with a
PUMP PERFORMANCE CHECK — The factory-installed
pumps in the 30RAP units are shipped with a single impeller
size available for that pump. The pump was selected based on
the flow and head requirements as provided to Carrier. It is not
uncommon for actual pump duty to be different than what was
anticipated at time of selection. In many cases, it may be desir-
able to make some field modifications to obtain optimum
pump performance.
Before any pump modifications are made, it is recommend-
ed that actual pump performance be verified and compared to
the applicable pump curve. See base unit installation instruc-
tions. This can be done in a variety of ways:
1. If pump impeller diameter is known:
a. Connect a differential pressure gage across the
pump at the ports provided on the pump volutes.
b. Read GPM from applicable impeller curve.
2. If pump impeller diameter is not known:
If pump impeller diameter has been trimmed and the size
is not known, it is necessary to determine which impeller
curve to read.
The easiest way to confirm pump performance is to
"dead-head" the pump and read the differential pressure
across the pressure ports on the pump. "Dead-heading"
can be done by shutting the circuit setter valve on the dis-
charge side of the pump.
NOTE: Although not all pumps can be safely "dead-
headed" centrifugal pumps (such as on the 30RAP units)
can be "dead-headed" for short amounts of time. It is rec-
ommended to keep the time short due to excessive heat
build-up in the pump.
Since the "dead-head" condition is a no-flow condition,
the head will correspond to the intersection of an impel-
ler curve with the vertical axis of the pump chart. The
correct impeller diameter is that which corresponds to the
measured head.
3. Once the impeller diameter is known, proceed as in
Step 1.
4. Water flow rate can be determined by using a differential
pressure gage with the Bell & Gossett circuit setter bal-
ance valve calculator. (This information is also provided
in the installation instructions.) This method will not di-
rectly measure pressure differential seen by the pump, but
can be used to "double-check" the pump measurement.
5. Verify that cable connections at the switch and at the ter-
minal block are secure.
6. For factory-installed hydronic system, verify that:
• All air has been purged from the system.
• Circuit setter balance valve has been correctly set.
7. Pump impeller has been improperly trimmed and is not
providing sufficient flow.
8. Wrong pump motor rotation. Pump must rotate clockwise
when viewed from motor end of pump.

PUMP MODIFICATIONS AND IMPELLER TRIMMING

— See applicable section in the Installation instructions.
RESET OF CHILLER WATER FLOW — See applicable sec-
tion in the Installation instructions.
CHANGING OF PUMP SEALS — See service instruction
manual provided with the hydronic package.
VFD OPERATION — For units with factory-installed VFD
(variable frequency drive) option, see service instruction manu-
al provided with the hydronic package.
68

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