Instruct The Customer Operator(S) - Carrier AquaEdge 19DV Series Start-Up, Operation And Maintenance Instructions Manual

Two-stage back-to-back centrifugal liquid chillers with pic6 controls and hfo r-1233zd(e) 50/60 hz
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Instruct the Customer Operator(s)

Ensure the operator understands all operating and maintenance
procedures. Point out the various chiller parts and explain their
function as part of the complete system.
EVAPORATOR-CONDENSER
High side float chamber, relief devices, refrigerant charging valve,
temperature sensor locations, pressure transducer locations,
Schrader fittings, waterboxes and tubes, and vents and drains.
MOTOR COMPRESSOR ASSEMBLY
Guide vane actuator, transmission, motor cooling system, tem-
perature and pressure sensors, sight glasses, motor temperature
sensors, and compressor serviceability.
COMPRESSOR LUBRICATION SYSTEM
Valves, dryers and filters, liquid level switch and inhibitor re-
claim system.
ECONOMIZER
Float valve, drain valve, Schrader fitting, damper valve.
CONTROL SYSTEM
CCN and LOCAL start, reset, menu, softkey functions, HMI
operation, occupancy schedule, set points, safety controls, and
auxiliary and optional controls.
PURGE
Check for potential leaks by monitoring purge hours in RUN-
TIME. Note changes over time.
AUXILIARY EQUIPMENT
Starters and disconnects, separate electrical sources, pumps,
and cooling tower.
DESCRIBE CHILLER CYCLES
Refrigerant, motor cooling, lubrication, and liquid reclaim.
REVIEW MAINTENANCE
Scheduled, routine, and extended shutdowns, importance of a
log sheet, importance of water treatment and tube cleaning, and
importance of maintaining a leak-free chiller.
SAFETY DEVICES AND PROCEDURES
Electrical disconnects, relief device inspection, and handling
refrigerant.
CHECK OPERATOR KNOWLEDGE
Start, stop, and shutdown procedures, safety and operating con-
trols, refrigerant charging, and job safety.
REVIEW THE START-UP, OPERATION, AND MAINTE-
NANCE MANUAL.
FINE TUNING VPF (VARIABLE PRIMARY FLOW)
SURGE PREVENTION
Figures 33-36 show how the parameters defined below will af-
fect the configured surge line. The menu can be found under

Main Menu
Configuration Menu
Config.
NOTE: Before tuning surge prevention, check for VFD (variable
frequency drive) speed limitation or capacity overrides. If the

Surge Correction
34
source of low capacity is found in one of these places, do not pro-
ceed with an attempt to tune the Surge Prevention configurations.
If capacity is not reached
and
1.
ACTUAL GUIDE VANE POSITION < GUIDE VANE
TRAVEL RANGE
and
2.
SURGE PREVENTION ACTIVE = YES (can be identified

in Main Menu
Maintenance Menu
and
3.
PERCENT LINE CURRENT < 100%
then the surge line is probably too conservative.
Note the following parameters from HMI when maximum
ACTUAL LINE CURRENT is achieved:
EVAPORATOR REFRIGERANT TEMP
EVAPORATOR PRESSURE
CONDENSER REFRIG TEMP
CONDENSER PRESSURE
ACTUAL GUIDE VANE POSITION
ACTUAL LINE CURRENT
The ACTIVE DELTA TSAT and the CALC REF DELTA
TSAT can be monitored on the Maintenance Menu
Correction screen. When ACTUAL DELTA TSAT exceeds
CALC REF DELTA TSAT + ENVELOPE LINE OFFSET
surge prevention will occur.
If ACTUAL GUIDE VANE POSITION is less than 30%, then
increase SURGE DELTA TSMIN in steps of 2ºF (1.2ºC) until
one of the three conditions listed above no longer applies. Do
not change SURGE DELTA TSMAX.
If ACTUAL GUIDE VANE POSITION is greater than 60%,
then increase SURGE DELTA TSMAX in steps of 2ºF (1.2ºC)
until cooling capacity is reached or one of conditions listed
above no longer applies. Do not change SURGE/HGBP DELTA
TSMIN.
If ACTUAL GUIDE VANE POSITION is more than 30%
AND less than 60%, then:
1.
Increase SURGE DELTA TSMIN in steps of 2ºF (1.2ºC).
2.
Increase SURGE DELTA TSMAX in steps of 2ºF (1.2ºC).
3.
Repeat Steps 1 and 2 until one of the conditions listed
above no longer applies.
NOTE: DELTA TSMIN should seldom need to be increased more
than 10 degrees above the selection program value. Likewise,
DELTA TSMAX rarely requires more than a 2ºF (1.2ºC) increase.
If surge is encountered then the controls surge prevention algo-
rithm surge line is probably too optimistic or high. Note fol-
lowing parameters from HMI at surge:
EVAPORATOR REFRIGERANT TEMP
EVAPORATOR PRESSURE
CONDENSER REFRIG TEMP
CONDENSER PRESSURE
ACTUAL GUIDE VANE POSITION
AVERAGE LINE CURRENT

Surge Correction)

Surge

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