Dunham-Bush ACDS, Installation, Operation & Maintanance Manual

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2.0 INSTALLATION
2.7.2.2 Series Chilled Water Flow Units
Units should be equally sized. The
upstream unit will carry a larger load
because it cools higher temperature
water. The thermostats sense inlet
water temperatures. (See figure 2.7D).
The number 1 unit thermostat will
unload or cycle off the packaged chiller
before unloading occurs of the Number
2 unit.
2.7.3 WATER QUALITY
Evaporators used in this packages is
made of steel and copper and are
suitable for operation with well-
maintained water systems. However, if
the water used in evaporator is corrosive,
high in mineral content or entrained
solids, the water can reduce the
performance and even damage the heat
exchangers. Therefore, it may be
necessary to obtain the service of a water
treatment consultant and to provide and
maintain water treatment. This is
particularly important with glycol systems
and with cooling tower loops.
2.8 ELECTRICAL
CONNECTIONS
2.8.1 GENERAL
All units are wired as completely as
possible at the factory prior to delivery.
The connections which must be made by
the installer are to the main power
source, starting equipment and
interlocking the satellite equipment. In
connecting power wiring to the unit, the
following precautions should be taken:
- All field wirings are to be in accordance
with the National Electrical Code and
state and local codes.
- All wirings are to be checked for damage
and all terminal connections are to be
tested for tightness. Unit terminal blocks
are to be connected with copper
conductors only and sized per ampacity
listed on unit data plate.
- The power supply should match the unit
nameplate in volts, phase and Hertz.
Voltage must be within ±10% of
nameplate value and voltage imbalance
between phases must not exceed 2%
2.9 REQUEST FOR START-UP
REPRESENTATIVE
Start-up service is an option upon request when
an order for the unit is placed. If you request for
start-up service, then after the installation has
been completed and checked, a written notice
shall be given to the Dunham-Bush
representative. Following receipt of written notice,
a representative will be sent to the customer. The
purchaser should have competent service and
operating personnel in attendance to assist in the
work involved, and also to be trained in the
operation and maintenance of this unit.
The representative will inspect the installation to
determine whether it meets Dunham-Bush
requirements, perform the initial start-up of the
installation determine whether it is in satisfactory
operating condition, and instruct specified
customer personnel in its operation and
maintenance for the length of time specified in the
purchase contract.