CAUTION:
To prevent personal injury wear safety
glasses, protective clothing, and gloves when handling
refrigerant and observe the following:
•Back-seating service valves are not equipped with
Schrader valves. Fully back seat (counterclockwise)
valve stem before removing gage port cap.
•Front-seating service valves are equipped with Schrader
valves.
CAUTION:
• 3-phase scroll compressors are rotation
sensitive.
• A flashing LED on phase monitor indicates reverse
rotation. (See Fig. 10 and Table 3.)
• This will not allow contactor to be energized.
• Disconnect power to unit and interchange 2 field wiring
leads on unit contactor.
Follow these steps to properly start up the system.
1. After system is evacuated, fully back seat (open) liquid and
vapor service valves.
2. Unit is shipped with valve stem(s) front seated (closed) and
caps installed. Replace stem caps after system is opened to
refrigerant flow. Replace caps finger tight and tighten with
wrench an additional 1/12 turn.
3. Close electrical disconnects to energize system.
4. Set room thermostat at desired temperature. Be sure set
point is below indoor ambient temperature.
5. Set room thermostat to COOL and fan control to ON or
AUTO mode, as desired. Operate unit for 15 minutes.
Check system refrigerant charge.
A.
SEQUENCE OF OPERATION
Turn on power to indoor and outdoor units. Transformer is
energized.
On a call for cooling, thermostat makes circuits R-Y and R-G. On
three phase models with scroll compressors, the units are equipped
with a phase monitor to detect in the incoming power is correctly
TABLE 1—REFRIGERANT CONNECTIONS AND RECOMMENDED LIQUID LINE AND VAPOR TUBE DIAMETERS (IN.)
UNIT
SIZE
LIQUID
VAPOR
VAPOR (LONG LINE)
Connection Diameter
Tube Diameter
Connection Diameter
Tube Diameter
Connection Diameter
Tube Diameter
018
3/8
3/8
5/8
5/8
5/8
5/8
024
3/8
3/8
5/8
5/8
5/8
3/4
030, 036
3/8
3/8
3/4
3/4
3/4
7/8
042, 048
3/8
3/8
7/8
7/8
7/8
1-1/8
060
3/8
3/8
7/8
1-1/8
7/8
1-1/8
NOTES:
1. Tube diameters are for lengths up to 50 ft. For tubing lengths greater than 50 ft horizontal, or greater than 20 ft vertical differential, consult the Application Guideline and
Service Manual—Air Conditioners and Heat Pumps Using Puron® Refrigerant.
2. Do not apply capillary tube indoor coils to these units.
TABLE 2—ACCESSORY USAGE
ACCESSORY
REQUIRED FOR
LOW-AMBIENT
APPLICATIONS
(BELOW 55°F)
REQUIRED FOR
LONG-LINE
APPLICATIONS*
(OVER 50 FT)
REQUIRED FOR
SEA COAST
APPLICATIONS
(WITHIN 2 MILES)
Crankcase Heater
Yes
Yes
No
Evaporator Freeze Thermostat
Yes
No
No
Winter Start Control
Yes†
No
No
Accumulator
No
No
No
Compressor Start Assist
Capacitor and Relay
Yes
Yes
No
MotorMaster® Control,
or
Low-Ambient Pressure Switch
Yes
No
No
Wind Baffle
See Low-Ambient Instructions
No
No
Coastal Filter
No
No
Yes
Support Feet
Recommended
No
Recommended
Liquid-Line Solenoid Valve
or
Hard Shutoff TXV
No
See Long-Line
Application
Guideline
No
Ball Bearing Fan Motor
Yes‡
No
No
* For tubing line sets between 50 and 175 ft, refer to Application Guideline and Service Manual—Air Conditioners and Heat Pumps Using Puron® Refrigerant.
† Only when low-pressure switch is used.
‡ Required for low-ambient controller (full modulation feature) and MotorMaster® Control only.
Fig. 9—Line Power Connections
A94025
DISCONNECT
PER N.E.C. AND/OR
LOCAL CODES
CONTACTOR
GROUND
LUG
FIELD GROUND
WIRING
FIELD POWER
WIRING
BLUE
3 PHASE ONLY
—6—
