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www.DaikinApplied.com 11
IOM 1264-1 • NAVIGATOR
®
MODEL WWV CHILLERS
Table 3: Glycol Performance Factors
%
Freeze Point
Flow
Pressure
Drop
°
F
°
C
Ethylene Glycol
10
26
-3.3
1.028
1.090
20
18
-7.8
1.059
1.216
30
7
-14
1.094
1.379
40
-7
-22
1.132
1.557
50
-28
-33
1.174
1.811
Propylene Glycol
10
26
-3.3
1.011
1.025
20
19
-7.2
1.030
1.150
30
9
-13
1.056
1.375
40
-5
-21
1.090
1.701
50
-27
-33
1.131
2.128
Ice Mode
Ice making chillers will run very cold fluid during off hours,
when energy is least expensive, to build a tank of ice. In ice
building mode, the unit will operate at full load until the shutoff
temperature setpoint is reached. Optional double evaporator
insulation is recommended for ice mode operation. The
standard controller software will require “ice” setpoint changes
and a digital signal into the controller is required to change to
the ice mode and back to standard cooling. Set points related
to ice mode can be found in
See Unit Level Set Points on page
21
and wiring connection points are shown in
Figure 10 on
page 14
.
Condenser Water Control
The minimum condenser inlet water temperature should not
be less than 60°F (15.6°C). If the water temperature is lower,
a method of condenser water temperature control will be
required. Cooling tower control is discussed beginning on
page
28.
Two-Way Bypass Valve Operation: A two-way regulating
control valve can control flow to ensure adequated condenser
water temperature. The unit controller can send a 0-10Vdc
signal to the valve to modulate its position.
Figure 4: Water Tower Connections - 2-Way Valve
Three-Way Bypass Valve Operation: To modulate the water
temperature in the condenser, install a three-way by-pass
valve.
Figure 5
shows how the three-way valve is applied in
the condenser water system. The three-way valve position can
be modulated by a 0-10Vdc signal from the unit controller to
regulates proper water temperature.
Figure 5: Water Tower Connections - 3-Way Valve
VFD Operating with a Condenser Water Pump: In place of a
valve, use a circulation pump controlled by an inverter.
The VFD speed may be controlled by an analog 0-10
Vdc signal issued by the controller according to the water
temperature entering the condenser.
Relief Valves
As a safety precaution and to meet code requirements, each
chiller is equipped with pressure relief valves located on the
condenser, evaporator, and compressor suction line(s) for the
purpose of relieving excessive refrigerant pressure (caused by
equipment malfunction, fire, etc.) to the atmosphere.
Table 4: Three-Way Relief Valve Data
Chiller
WWV
Relief Valve
Evaporator
Condenser
Location
Top of vessel
Top of vessel
Pressure Setting (psi)
225
300
Discharge Cap.(lb/min air) 84.4
111
Qty
1 set
1 set
Connection Size
1.0-inch female
NPT
1.0-inch female
NPT
Building codes require that relief valves be vented to the
outside of a building. Relief piping connections to the relief
valves must have flexible connectors.
Remove plastic shipping plugs (if installed) from the inside of
the valves prior to making pipe connections. Whenever vent
piping is installed, the lines must be in accordance with local
Summary of Contents for Navigator WWV
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