Carrier Gemini 38AU Series Installation, Start-Up And Service Instructions Manual page 12

glasses in a single circuit application. One filter drier and sight
glass may be installed at A locations (see Fig. 9) or 2 filter driers
and sight glasses may be installed at B locations (see Fig. 9 and
10).
Select the filter drier for maximum unit capacity and minimum
pressure drop. Complete the refrigerant piping from the indoor
unit to the outdoor unit before opening the liquid and suction lines
at the outdoor unit.
INSTALL LIQUID LINE SOLENOID VALVE
It is recommended that a solenoid valve be placed in the main liq-
uid line (see Fig. 9 and 10) between the condensing unit and the
evaporator coil. Locate the solenoid valve at the outlet end of the
liquid line, near the evaporator coil connections, with flow direc-
tion arrow pointed at the evaporator coil. Refer to Table 13. (A liq-
uid line solenoid valve is required when the liquid line length ex-
ceeds 75 ft [23 m].) This valve prevents refrigerant migration
(which causes oil dilution) to the compressor during the off cycle,
at low outdoor ambient temperatures. Wire the solenoid in parallel
with the compressor contactor coil (see Fig. 9 and 10). This means
of electrical control is referred to as solenoid drop control.
TXV
INDOOR
SENSING
COIL CKT BULB
AIRFLOW 15 DIAMS
10
MIN
DIAMS
SINGLE CIRCUIT COIL PIPING CONFIGURATION
FOR SINGLE COMPRESSOR CONDENSING UNITS
TXV
INDOOR SENSING
COIL CKT 2 BULB
AIRFLOW 15 DIAMS
10
MIN
DIAMS
8 DIAMS
TXV
SENSING
INDOOR
BULB
COIL CKT 1
AIRFLOW 15 DIAMS
10
MIN
DIAMS
DUAL CIRCUIT COIL PIPING CONFIGURATION
FOR SINGLE COMPRESSOR CONDENSING UNITS
Fig. 9 — Location of Sight Glass(es) and Filter Driers
Typical 38AUZ Systems
EQUALIZER LINE
SIGHT GLASS
A LOCATION
FILTER DRIER
A LOCATION
TXV
8 DIAMS
MIN
LIQUID LINE
SOLENOID
VALVE
EQUALIZER LINE
SIGHT GLASS
A LOCATION
TXV FILTER DRIER
A LOCATION
CKT 2
SIGHT
MIN
GLASSES
B LOCATION
FILTER
LIQUID LINE
DRIERS
SOLENOID
B LOCATION
VALVE
TXV
CKT 1
8 DIAMS
MIN
TXV
SENSING
BULB
AIRFLOW
15 DIAMS
10
MIN
DIAMS
TXV
SENSING
BULB
AIRFLOW 15 DIAMS
10
MIN
DIAMS
SUCTION
CIRCUIT 1
SUCTION
CIRCUIT 2
DUAL CIRCUIT COIL PIPING CONFIGURATION
FOR TWO CIRCUIT CONDENSING UNITS
Fig. 10 — Location of Sight Glasses and Filter Driers
Typical 38AUD Systems
Solenoid Drop Control Wiring
Control the power to the liquid line solenoid through a Solenoid
Valve Relay (SVR) in all units. Use part number HN61PC005
(field-supplied, installed). 38AUZ unit requires one SVR; 38AUD
unit requires two relays.
A unit with two liquid line solenoid valves also requires a separate
control power transformer for the liquid solenoid valve loads. Se-
lect TRAN3 transformer part number according to unit power
supply.
QTY RELAY SVR QTY
MODEL
LSV - PART NUMBER
1 1 — HN61PC005
38AUZ
2 2 — HN61PC005
38AUDA,B 2 2 — HN61PC005
38AUDC 2 1 — HN61PC005*
LEGEND
LSV — Liquid Solenoid Valve
SVR — Solenoid Valve Relay
N/R — Not Required
N/R # — Not Required / Factory Installed
* Install as SVR-2 (SVR-1 is factory-installed).
Mount the SVR (and transformer TRAN3 when used) in unit con-
trol box. Connect per wiring schematic label on unit.
NOTE: TRAN3 is provided with the HGBP factory installed op-
tion for 38AUDC12 units.
12
EQUALIZER LINE
TXV
CKT 2
8 DIAMS
MIN
SIGHT
GLASSES
LIQUID LINE
SOLENOID VALVE
FILTER
CIRCUIT 2
DRIERS
TXV
CKT 1
8 DIAMS
MIN
LIQUID LINE
SOLENOID VALVE
CIRCUIT 1
TRAN3 PRIMARY V:
PART NUMBER
N/R
208/230V: HT01BD202
460V: HT01BD702
575V: HT01BD902
N/R #