Motor Cooling System; Tracer Adaptiview Display - Trane CVHE Installation, Operation And Maintenance Manual

WARNING
Hot Surface!
Failure to use caution while working on the oil system
could result in severe burns. Oil system temperature
could exceed 150°F (65.6°C).
To ensure proper lubrication and prevent refrigerant from
condensing in the oil tank, a 750-watt heater is in a well in
the oil tank. The heater is used to warm the oil while the
unit is off. With the default settings, the oil heater is de-
energized when the unit starts. The heater energizes as
needed to maintain 140°F to 145°F (60.0°C to 62.8°C) when
the chiller is not running.
When the chiller is operating, the temperature of the oil
tank is typically 100°F to 160°F (37.8°C to 71.1°C). The oil
return lines from the thrust and journal bearings, transport
oil and some seal leakage refrigerant. The oil return lines
are routed into a manifold and separator under the motor.
Gas flow exits the top of the manifold and is vented to the
evaporator. Oil exits the bottom of the manifold and
returns to the tank. Separation of the seal leakage gas in
the separator keeps this gas out of the tank.
A dual eductor system is used to reclaim oil from the
suction cover and the evaporator, and deposit it back into
the oil tank. These eductors use high-pressure condenser
gas to draw the oil from the suction cover and evaporator
to the eductors and then discharged into the oil tank. The
evaporator eductor line has a shut-off valve mounted by
the evaporator. The shut-off valve will be set during
commissioning but may be adjusted later by a qualified
technician, as necessary for oil return. A normal operating
setting for the valve may range from full closed to two
turns open.
Note: Depending on operating conditions, the oil sump's
normal operating oil level may vary from just
below the bottom sight glass to near the top of the
upper sight glass.
Liquid refrigerant is used to cool the oil supply to both the
thrust bearing and journal bearings. On refrigerant pump
units the oil cooler is located inside the economizer and
uses refrigerant passing from the condenser to evaporator
to cool the oil. Oil leaves the oil cooler and flows to both
the thrust and journal bearings.

Motor Cooling System

Compressor motors are cooled with liquid refrigerant (see
Figure 36, p. 58). The refrigerant pump is located on the
front of the oil tank (motor inside the oil tank). The
refrigerant pump inlet is connected to the well at the
bottom of the condenser. The connection is on the side
where a weir ensures a preferential supply of liquid
refrigerant. Refrigerant is delivered to the motor via the
pump. An in-line filter is installed (replace the in-line filter
only with major service). Motor refrigerant drain lines are
routed to the condenser.
CVHE-SVX02H-EN

Tracer AdaptiView Display

Information is tailored to operators, service technicians,
and owners.
When operating a chiller, there is specific information you
need on a day-to-day basis—setpoints, limits, diagnostic
information, and reports.
Day-to-day operational information is presented at the
display. Logically organized groups of information—
chiller modes of operation, active diagnostics, settings
and reports put information conveniently at your
fingertips. For more information, refer to Tracer
AdaptiView™ Display for Water-Cooled CenTraVac™
Chillers Operations Guide (CTV-SVU01*-EN, or the most
recent version).
Operating Principles
59