AAON SA-028, Installation Operation & Maintenance

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Table of Contents

Safety .............................................................................................................................................. 6

SA Series Feature String Nomenclature ....................................................................................... 11

General Information ...................................................................................................................... 16

Codes and Ordinances ............................................................................................................... 16

Receiving Unit ........................................................................................................................... 16

Storage ....................................................................................................................................... 17

Direct Expansion (DX) Systems ............................................................................................... 17

Wiring Diagrams ....................................................................................................................... 18

Condensate Drain Pans .............................................................................................................. 18

Unit Size .................................................................................................................................... 18

Installation..................................................................................................................................... 19

Locating the Unit ....................................................................................................................... 19

Lifting and Handling the Unit ....................................................................................................... 19

Split Unit Assembly .................................................................................................................. 26

Refrigerant-to-Water Heat Exchanger ...................................................................................... 29

Open Loop Applications ........................................................................................................ 29

Freezing Water in the Heat Exchanger .................................................................................. 29

Water Piping .......................................................................................................................... 30

Brazed Plate Heat Exchanger Cleaning ................................................................................. 33

Electrical .................................................................................................................................... 33

Cutting Electrical Openings ................................................................................................... 34

Thermostat Control Wiring .................................................................................................... 35

Duct Connection ........................................................................................................................ 36

Condensate Drain Piping ........................................................................................................... 36

Waterside Economizer .............................................................................................................. 37

Hot Water Coil .......................................................................................................................... 41

Chilled Water Coil .................................................................................................................... 41

Startup ........................................................................................................................................... 41

Supply Fans ............................................................................................................................... 41

Supply Fan Spring Isolator Adjustment ................................................................................ 41

Supply Fan Removal .............................................................................................................. 43

Fan Airflow Adjustment ........................................................................................................ 43

Filters ......................................................................................................................................... 45

Adjusting Refrigerant Charge ................................................................................................... 45

Freeze Stat Startup .................................................................................................................... 47

Operation....................................................................................................................................... 48

Steam or Hot Water Preheating Operation ................................................................................ 48

Chilled Water or Non-Compressorized DX Cooling Operation ............................................... 48

Packaged DX Cooling Operation and Control .......................................................................... 48

Maintenance .................................................................................................................................. 48

DX Cooling ............................................................................................................................... 48

Condensate Drain Pans .............................................................................................................. 48

E-Coated Coil Cleaning ............................................................................................................ 49

Recommended Coil Cleaner .................................................................................................. 49