Trane RAUC-IOM-15, Installation & Maintenance Instructions Manual

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Pipe Unions
Use pipe unions to simplify disassembly for system service.
Use vibration eliminators to prevent transmitting vibrations
through the water lines
Thermometers
Install thermometers in the lines to monitor the evaporator
entering and leaving water temperatures.
Balancing Valves
Install a balancing cock (valve) in the leaving water line. It
will be used to establish a balanced flow.
Note: Both the entering and leaving water lines
should have shutoff valves installed to isolate the
evaporator for service.
Strainer
Install a pipe strainer in the water return line to protect the
components from entrapped debris.
Chiller Drain
The chiller drain should be piped to a suitable drain facility
to facilitate evaporator draining during service or shutdown
procedures. Provide a shutoff valve in the drain line.
Note: The EVP chiller ships without the drain plug
installed. If drain piping is not installed, remove the
drain plug from the EVP control panel and install it
in the drain port before filling the system with
water.
Chiller Flow Switch
Install a flow switch or other flow sensing device, illustrated
in Figure 3-9, to prevent or stop the compressor operation if
the water flow drops off drastically. A flow switch ships with
a each unit when a “T” is included in the miscellaneous digit
of the model number. Locate the device in the chilled water
supply line (water outlet) as shown in Figure 3-8. Refer to
the field wiring and unit schematics for the flow switch elec-
trical interlock connections.
Water Temperature Sensor
The Temperature Sensor and Sensor-well must be installed
using the threaded connection provided on the chiller barrel
leaving water pipe. Both devices are shipped inside the
unit’s shipwith location. Thermal paste must be used when
installing the sensor into the sensor-well. Refer to Figure 3-
2B for the sensor location and dimensional data.
Note: Failure to use thermal paste could result in
erratic temperature sensing resulting in equipment
damage.
Chilled Water Piping
Evaporator water inlet and outlet types, sizes and locations
are shown in Figure 3-2B. Refer to the operating GPM pa-
rameters listed in Table 3-3 when determining flow and pip-
ing requirements. Figure 3-8 illustrates the typical water pip-
ing components for chiller applications. Refer to this illustra-
tion while following the discussion on the various piping
components.
Isolate the water pumps from the system to avoid vibration
transmission. To minimize heat gain and prevent condensa-
tion, insulate all water piping. Use an appropriate pipe seal-
ant on all threaded connections.
Table 3-3
GPM vs Pressure Drop
Chiller Pressure Drop **
GPM* Chiller Size
80 Ton 100 Ton 120 Ton
100 4.5
120 6.5 3.2
140 8.7 4.3 3.2
160 11.2 5.6 4.1
180 14.1 7.0 5.2
200 17.2 8.5 6.3
240 24.8 12.2 9.0
280 16.3 12.0
320 21.0 15.8
360 26.0 19.7
400 24.0
* - Gallons Per Minute
** - All Pressure Drops are in Feet of Water
= Beyond the working limits of the barrel
Air Vents
A vent port is located on top of the chiller near the return
end. Additional vents must be installed at high points in the
piping system to facilitate air purging during the filling pro-
cess.
Water Pressure Gauges
Install pressure gauge(s) to monitor the entering and leav-
ing chilled water pressure.
Note: To prevent evaporator damage, do not
exceed 150 psig evaporator pressure.
Water Shutoff Valves
Provide shutoff valves in the “Supply” and “Return” pipe
near the chiller so the gauge(s), thermostats, sensors,
strainer, etc., can be isolated during service.
Installation (Continued)