Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 04-53380032-01
Printed in U.S.A.
Form 38AU-7-14-04SI
Pg 1
12-19
Replaces: 38AU-7-14-03SI
Installation, Start-Up and Service Instructions
CONTENTS
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . 1
INSTALLATION GUIDELINES . . . . . . . . . . . . . . . . . . . 2
Replacement/Retrofit —
R-22 to Puron Refrigerant . . . . . . . . . . . . . . . . . . . 2
Rated Indoor Airflow (cfm) . . . . . . . . . . . . . . . . . . . . . 2
Identify Factory Options . . . . . . . . . . . . . . . . . . . . . . . 3
Matching 38AU Model to Evaporator Coil . . . . . . . . . 3
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Jobsite Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Step 1 — Plan for Unit Location . . . . . . . . . . . . . . . . 6
Step 2 — Complete Pre-Installation Checks . . . . . . . 7
Step 3 — Prepare Unit Mounting Support . . . . . . . . 7
Step 4 — Rig and Mount the Unit . . . . . . . . . . . . . . . 7
Step 5 — Determine Refrigerant Line Sizes . . . . . . . 7
Suction Riser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Step 6 — Complete Refrigerant Piping
Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Step 7 — Install Accessories . . . . . . . . . . . . . . . . . . 13
Step 8 — Complete Electrical Connections . . . . . . 14
Step 9 — Wind Baffles for Low Ambient Control . . 20
PRE-START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Turn On Crankcase Heater . . . . . . . . . . . . . . . . . . . . 20
Preliminary Charge . . . . . . . . . . . . . . . . . . . . . . . . . . 20
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Preliminary Checks . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Start Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
OPERATING SEQUENCE . . . . . . . . . . . . . . . . . . . . . 29
Base Unit Controls . . . . . . . . . . . . . . . . . . . . . . . . . . 29
38AUDC with SVR Relays . . . . . . . . . . . . . . . . . . . . . 30
All Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Quarterly Inspection
(and 30 days after initial start) . . . . . . . . . . . . . . . 31
Seasonal Maintenance . . . . . . . . . . . . . . . . . . . . . . . 31
SERVICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Refrigeration System . . . . . . . . . . . . . . . . . . . . . . . . 31
Comfort Alert Diagnostic Module . . . . . . . . . . . . . . 33
Compressor Protection . . . . . . . . . . . . . . . . . . . . . . 35
Fastener Torque Values . . . . . . . . . . . . . . . . . . . . . . 36
TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . 36
APPENDIX A — AIR CONDITIONER AND HEAT PUMP
WITH PURON – QUICK REFERENCE GUIDE . . . 38
APPENDIX B — WIRING DIAGRAMS . . . . . . . . . . . . 38
APPENDIX C — LOW AMBIENT OPTION . . . . . . . . 50
START-UP CHECKLIST . . . . . . . . . . . . . . . . . . . . . CL-1
SAFETY CONSIDERATIONS
Improper installation, adjustment, alteration, service,
maintenance, or use can cause explosion, fire, electrical shock or
other conditions which may cause personal injury or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory-authorized kits or accessories
when modifying this product. Refer to the individual instructions
packaged with the kits or accessories when installing.
Follow all safety codes. Wear safety glasses and work gloves. Use
quenching cloths for brazing operations and have a fire
extinguisher available. Read these instructions thoroughly and
follow all warnings or cautions attached to the unit. Consult local
building codes and appropriate national electrical codes (in USA,
ANSI/NFPA70, National Electrical Code (NEC); in Canada, CSA
C22.1) for special requirements.
It is important to recognize safety information. This is the safety-
alert symbol
. When you see this symbol on the unit and in
instructions or manuals, be alert to the potential for personal
injury.
Understand the signal words DANGER, WARNING, CAUTION,
and NOTE. These words are used with the safety-alert symbol.
DANGER identifies the most serious hazards which
will
result in
severe personal injury or death. WARNING signifies hazards
which
could
result in personal injury or death. CAUTION is used
to identify unsafe practices, which
may
result in minor personal
injury or product and property damage. NOTE is used to highlight
suggestions which
will
result in enhanced installation, reliability,
or operation.
DANGER
ELECTRICAL SHOCK HAZARD
Failure to follow this warning will result in personal injury or
death.
Before performing service or maintenance operations on unit,
turn off main power switch to unit and install lock(s) and lock-
out tag(s). Ensure electrical service to rooftop unit agrees with
voltage and amperage listed on the unit rating plate. Unit may
have more than one power switch.
WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal injury,
death and/or equipment damage.
R-410A refrigerant systems operate at higher pressures than
standard R-22 systems. Do not use R-22 service equipment or
components on R-410A refrigerant equipment.
Gemini™
38AU**07-14
Air-Cooled Condensing Units
with Puron
®
(R-410A) Refrigerant
