Carrier 19XL CHILLER FAMILIARIZATION (Fig. 1, 2A, and 2B) Chiller Information Plate , SystemComponents , Cooler , Condenser , Motor-Compressor , Control Center , Factory-MountedStarter (Optional) , Storage Vessel (Optional) , REFRIGERATION CYCLE, MOTOR/OIL REFRIGERATION COOLING CYCLE

CHILLER FAMILIARIZATION(Fig. 1, 2A, and 2B)

Chiller Information Plate — The information plate

is located on the right side of the chiller control center

panel.

SystemComponents — Thecomponents include the

cooler and condenser heat exchangers in separate vessels,

motor-compressor, lubrication package, control center,and

motorstarter. All connections from pressure vessels have ex-

ternalthreads to enable each component to be pressure tested

with a threaded pipe cap during factory assembly.

Cooler — This vessel (also known as the evaporator) is

located underneath the compressor. The cooler is main-

tained at lower temperature/pressure so that evaporating

refrigerant can remove heat from water ﬂowing through its

internal tubes.

Condenser — The condenser operates at a higher

temperature/pressure than the cooler,and has water ﬂowing

through its internal tubes in order to remove heat from the

refrigerant.

Motor-Compressor— Thiscomponent maintains sys-

tem temperature/pressure differences and moves the heat

carrying refrigerant from the cooler to the condenser.

Control Center — The control center is the user inter-

face for controlling the chiller. It regulates the chiller’s

capacityas required to maintain proper leaving chilled water

temperature. The control center:

• registers cooler, condenser, and lubricating system

pressures

• shows chiller operating condition and alarm shutdown

conditions

• records the total chiller operating hours

• sequences chiller start, stop, and recycle under micro-

processor control

• provides access to other CCN (Carrier Comfort Network)

devices

Factory-MountedStarter (Optional) — Thestarter

allows the proper start and disconnect of electrical energy

for the compressor-motor, oil pump, oil heater,and control

panels.

Storage Vessel (Optional) — There are 2 sizes

of storage vessels available. The vessels have double relief

valves, a magnetically coupled dial-type refrigerant level

gage, a one-inch FPT drain valve, and a

⁄

-in. male ﬂare

vapor connection for the pumpout unit. A30-in.-0-400 psi

(–101-0-2750 kPa) gage also is supplied with each unit.

NOTE: If a storage vessel is not used at the jobsite, factory-

installed isolation valves on the chiller may be used to iso-

late the chiller charge in either the cooler or condenser.

An optional pumpout compressor system is used to transfer

refrigerant from vessel to vessel.

REFRIGERATION CYCLE

Thecompressor continuously draws refrigerant vapor from

thecooler, at a rate set by the amount of guide vane opening.

Asthe compressor suction reduces the pressure in the cooler,

the remaining refrigerant boils at a fairly low temperature

(typically 38 to 42 F [3 to 6 C]). The energy required for

boilingis obtained from the water ﬂowing through the cooler

tubes. With heat energy removed, the water becomes cold

enough for use in an air conditioning circuit or process liq-

uid cooling.

After taking heat from the water, the refrigerant vapor

is compressed. Compression adds still more heat energy

and the refrigerant is quite warm (typically 98 to 102 F

[37to 40 C]) when it is discharged from the compressor into

the condenser.

Relatively cool (typically 65 to 90 F [18 to 32 C]) water

ﬂowing into the condenser tubes removes heat from the

refrigerant and the vapor condenses to liquid.

The liquid refrigerant passes through oriﬁces into the

FLASC(Flash Subcooler) chamber (Fig. 3). Since the FLASC

chamber is at a lower pressure, part of the liquid refrigerant

ﬂashes to vapor, thereby cooling the remaining liquid. The

FLASC vapor is recondensed on the tubes which are cooled

by entering condenser water. The liquid drains into a ﬂoat

chamber between the FLASC chamber and cooler. Here a

ﬂoat valve forms a liquid seal to keep FLASC chamber

vaporfrom entering the cooler. When liquid refrigerant passes

through the valve, some of it ﬂashes to vapor in the reduced

pressureon the cooler side. In ﬂashing, it removes heat from

theremaining liquid. The refrigerant is now at a temperature

and pressure at which the cycle began.

MOTOR/OIL REFRIGERATIONCOOLING CYCLE

The motor and the lubricating oil are cooled by liquid

refrigerant taken from the bottom of the condenser vessel

(Fig. 3). Flow of refrigerant is maintained by the pressure

differentialthat exists due to compressor operation. After the

refrigerant ﬂows past an isolation valve, an in-line

ﬁlter, and a sight glass/moisture indicator, the ﬂow is split

between motor cooling and oil cooling systems.

Flow to the motor ﬂows through an oriﬁce and into the

motor.There is also another oriﬁce and a solenoid valve which

will open if additional motor cooling is required. Once past

the oriﬁce, the refrigerant is directed over the motor by a

spray nozzle. The refrigerant collects in the bottom of the

motorcasing and then is drained back into the cooler through

the motor refrigerant drain line.A back pressure valve or an

oriﬁce in this line maintains a higher pressure in the motor

shell than in the cooler/oil sump. The motor is protected by

atemperature sensor imbedded in the stator windings. Higher

motor temperatures (above 125 F [51 C]) energize a sole-

noid to provide additional motor cooling.A further increase

in temperature past the motor override set point will over-

ride the temperature capacity control to hold, and if the

motor temperature rises 10° F (5.5° C) above this set point,

willclose the inlet guide vanes. If the temperature rises above

the safety limit, the compressor will shut down.

Fig. 1 — 19XL Identiﬁcation