Daikin Magnitude WME092CD User Manual

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www.DaikinApplied.com 25 IOM 1266-2 • MAGNITUDE
®
MODEL WME CHILLERS
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Operator Responsibilities
It is important that the operator become familiar with the
equipment and the system before attempting operation. During
the initial startup of the chiller, the Daikin Applied technician will
be available to answer any questions and instruct the proper
operating procedures. It is recommended that the operator
maintain an operating log for each individual chiller unit. In
addition, a separate maintenance log should be kept of the
periodic maintenance and servicing activities.
Operator Schools
Training courses for Magnitude
®
Centrifugal Maintenance and
Operation are held throughout the year at the Daikin Learning
Institute in Verona, Virginia. The school curriculum includes
instruction on basic refrigeration, MicroTech
®
controllers and
troubleshooting, enhancing chiller efciency and reliability,
system components, and other related subjects. For more
information, visit us at www.DaikinApplied.com and click on
Training or call the Training Department. Refer to the back
cover of this manual for contact information.
Sequence of Unit Operation
A general chiller sequence of operation is outlined below
for Magnitude
®
Model WME chillers. A separate sequence
is provided for single and dual compressor units. Certain
conditions and chiller alarms may alter the sequence, but the
chiller’s objective is to achieve the target temperature of the
leaving water.
Placing two chillers in series evaporator operation or series-
counterow conguration is possible and requires connecting
an Ethernet cable between the unit control panels and
reassigning a temperature sensor. Communication directly
between the chillers allows better control of leaving water
temperature while balancing the load. Contact a Daikin Applied
representative for specic details.
Single Compressor Units
The following sequence of operation applies to Magnitude
®
Model WME chillers with a single compressor.
1. Chiller enabled
With the chiller enabled via its onboard interlocks
and selected external control source, it will start the
evaporator pump and check for ow and chiller load.
2. Water ow and load proven
Once evaporator ow has been conrmed and the chiller
load proven, the sequence for starting the compressor
will begin.
3. Compressor shaft levitation
The magnetic bearings are activated and correct shaft
position is veried.
4. Condenser pump start
The condenser pump is commanded to start and water
ow is conrmed. Electronic Expansion Valve (EXV)
must be open
5. Compressor start
The compressor is started and comes up to the
calculated Start RPM and Inlet Guide Vane (IGV). From
this point the vanes are opened and then speed is
increased to match the cooling load.
6. Compressor loading
As building load increases, the compressor will load
up maximizing the IGV position and impeller speed.
Maximum capacity at a given operating condition can be
found when the compressor reaches its Maximum RPM,
maximum allowed % RLA or power limitation.
7. Compressor unloading
As load decreases, the compressor will unload to sustain
the water temperature setpoint by reducing speed until
the minimum speed limit has been reached. If further
unloading is required, the IGV assemblies will close as
required to satisfy the load. Further capacity reduction is
accomplished by opening the Part Load Balance Valve
(PLBV).
8. Chiller shutdown
The compressor will adjust capacity to manage the
chiller load and will shut off when the load reduces below
the compressor's minimum capacity and the leaving
water temperature goes below setpoint and reaches the
stop delta temperature. Anytime the chiller is disabled,
it will perform an orderly unload and shutdown of the
compressor.
Dual Compressor Units
The following sequence of operation applies to Magnitude
®
Model WME chillers with dual compressors.
1. Chiller enabled
With the chiller enabled via its onboard interlocks
and selected external control source, it will start the
evaporator pump and check for ow and chiller load.
2. Water ow and load proven
Once evaporator ow has been conrmed and the
chiller load proven, the sequence for starting the Lead
compressor will begin. Auto lead-lag logic will determine
which compressor to start rst based on number of
starts. For 099 models, the smaller compressor will start
rst.
3. Compressor shaft levitation
The magnetic bearings are activated and correct shaft
position is veried.
4. Condenser pump start
The condenser pump is commanded to start and water
ow is conrmed. EXV must be open.

Daikin Magnitude WME092CD Specifications

General

Brand	Daikin
Model	Magnitude WME092CD
Category	Chiller
Language	English