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Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 04-53480239-01
Printed in U.S.A.
Form 48/50A-14T
Pg CL-1
5-19
Replaces: 48/50A-13T
UNIT START-UP CHECKLIST
MODEL NO.: _________________________________
SERIAL NO.: _____________________________________
SOFTWARE VERSION _________________________
TECHNICIAN: ____________________________________
DATE: _______________________________________
PRE-START-UP:
VERIFY THAT ALL PACKING MATERIALS HAVE BEEN REMOVED FROM UNIT
REMOVE ALL COMPRESSOR SHIPPING HOLDDOWN BOLTS AND BRACKETS PER INSTRUCTIONS
VERIFY INSTALLATION OF ECONOMIZER HOOD PER INSTRUCTIONS
(including relocation of OAT sensor if necessary)
VERIFY INSTALLATION OF ALL OPTIONS AND ACCESSORIES
VERIFY PROPER INSTALLATION AND LOCATION OF STATIC PRESSURE TRANSDUCERS
(Supply Duct and Building Pressure when applicable)
VERIFY THAT ALL ELECTRICAL CONNECTIONS AND TERMINALS ARE TIGHT
VERIFY INSTALLATION AND LOCATION OF LAT SENSORS (multi-staged gas, SCR electric, hydronic heat only)
CHECK GAS PIPING FOR LEAKS (48A ONLY)
CHECK THAT RETURN-AIR FILTER AND OUTDOOR-AIR FILTERS ARE CLEAN AND IN PLACE
VERIFY THAT UNIT IS LEVEL WITHIN TOLERANCES FOR PROPER CONDENSATE DRAINAGE
CHECK FAN WHEELS AND PROPELLERS FOR LOCATION IN HOUSING/ORIFICE, AND SETSCREW IS TIGHT
VERIFY THAT FAN SHEAVES ARE ALIGNED AND BELTS ARE PROPERLY TENSIONED
VERIFY THAT SUCTION, DISCHARGE, AND LIQUID SERVICE VALVES ON EACH CIRCUIT ARE OPEN
VERIFY THAT CRANKCASE HEATERS HAVE BEEN ON 24 HOURS BEFORE START-UP
START-UP:
ELECTRICAL
SUPPLY VOLTAGE
L1-L2
__________
L2-L3 _________
L3-L1
__________
COMPRESSOR AMPS — COMPRESSOR NO. 1 L1
_________
L2
___________
L3 _________
COMPRESSOR AMPS — COMPRESSOR NO. 2 L1
_________
L2
___________
L3 _________
SUPPLY FANS AMPS
(CV/SAV)
________
EXHAUST FAN AMPS ___________
(VAV)
_________ *
*VAV fan supply amps reading must be taken with a true RMS meter for accurate readings.
TEMPERATURES
OUTDOOR-AIR TEMPERATURE
_________ F DB (Dry Bulb)
RETURN-AIR TEMPERATURE
_________ F DB _________ F WB (Wet Bulb)
COOLING SUPPLY AIR
_________ F
GAS HEAT SUPPLY AIR
_________ F (48A ONLY)
ELECTRIC HEAT SUPPLY AIR
_________ F (50A ONLY, IF EQUIPPED)
NOTE: To avoid injury to personnel and damage to equipment or
property when completing the procedures listed in this start-up
checklist, use good judgment, follow safe practices, and adhere
to the safety considerations/information as outlined in preced-
ing sections of this Controls, Start-Up, Operation, Service, and
Troubleshooting document.
Summary of Contents for WEATHERMAKER 48A2020
Page 112: ...112 Fig 20 Typical Main Control Box Wiring Schematic 48 50A Units ...
Page 113: ...113 Fig 21 Typical Auxiliary Control Box Wiring Schematic ...
Page 114: ...114 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown ...
Page 115: ...115 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown TO NEXT PAGE ...
Page 116: ...116 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont ...
Page 117: ...117 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown ...
Page 118: ...118 Fig 25 Typical Controls Option Wiring Schematic SW1 SW2 OR DEHUMIDIFY SWITCH ...
Page 119: ...119 Fig 26 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown ...
Page 120: ...120 Fig 27 Typical Power Schematic of Greenspeed Low Ambient Option 48 50A 060 Unit Shown ...
Page 121: ...121 Fig 28 Typical Small Chassis Component Location Size 020 035 Units ...
Page 122: ...122 Fig 29 Typical Large Chassis Component Locations Size 040 060 Units ...
Page 185: ...185 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...