Q 2pj, Ma q l2jlml-g – Carrier 30GT User Manual

Page 2

Advertising

UNITS

and

(See Fig. 1.)

Line

Connect the field-supplied line to the

factory-provided stubs in the discharge line

the

circuit no. 1 compressor and in the

no.

line,

between expansion valve and cooler (stubs are sealed

from factory).

Bypass Valve

Install the valve in the

line as

close to the cooler as possible. This

liquid

storage between valve and cooler when valve is closed

and prevents flood of liquid refrigerant when the valve
opens.

ensure proper closing, install the bypass valve

in a horizontal section of the bypass line, with the pilot

valve installed vertically (coil on top).
Solenoid Pilot Valve

Install on the bypass valve at the

external equalizer

OD sweat connection). The

outlet side of the pilot valve is a

SAE thread. Run

OD tube from this connection to the thermo-

static expansion valve (TXV) equalizer line, If the

connection is made directly to the TXV, use a

female flare tee. If the connection is made into

the equalizer line, use a standard

FL tee.

UNITS,

(See Fig. 2.)

Bypass Line

Install field-supplied line between the

header on inlet side of lead coil and the entrance to the
cooler. Two factory-sealed stubs are provided in each

circuit, one on the lead coil header and one on the liquid
line between the Flotronic expansion valve (EXV) and

the cooler.
NOTE: The 30GB 1

units have 2 stubs in the high

side of each circuit, one on each lead coil header; it is

necessary to connect piping to only one of these stubs.
Bvpass Valve

Install the valve in the bypass line as

close to the cooler as possible. This minimizes liquid

storage between the valve and cooler when valve is
closed and prevents flood of liquid refrigerant when the

valve opens. To ensure proper closing, install the by ass

valve in a horizontal section of the bypass line, wit

the

pilot valve installed vertically (coil on top).

Solenoid Pilot Valve

Install on the bypass valve at

the external equalizer. The outlet side of the pilot valve is
a

SAE thread. Run a

OD tube from this

connection to the suction valve of the lead compressor

in the circuit.

SUCTION LINE VALVE

EXV- ELECTRONIC EXPANSION VALVE
TXV- THERMOSTATIC EXPANSION VALVE

PIPING

NOTE: Circuit 2 should be piped same as circuit 1. The

tube should be connected to the lead compressor in both circuits.

CKT

q 2pJ

0 6 0

0 7 5 , 0 8 0

090,100

110,125

CKT

q l2Jlml-g

2 0 0

Compressor numbers, viewed facing compressor side of unit.

Fig. 2

Schematic Piping;

with Electronic Controls (Flotronic)

Advertising