Table of Contents
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1 ................................................................................................. 7
1. Warning .................................................................................................................................. 7
2. System introduction and dimensions ........................................................................................ 8
2.1. System introduction ...................................................................................................... 8
2.2. Dimensions ................................................................................................................. 10
3. Inspect shipment .................................................................................................................... 12
4. Disclaimer ............................................................................................................................. 13
5. Safety precautions ................................................................................................................. 14
5.1. Before installation and electric work .............................................................................. 14
5.2. Devices that use R410A refrigerant .............................................................................. 22
5.3. Before getting started .................................................................................................. 23
5.4. Before getting PAA unit installed (moved) - electrical work ............................................. 28
5.5. Before starting the test run ........................................................................................... 30
5.6. After installation and test run ........................................................................................ 31
5.7. To dispose the PAA unit ............................................................................................... 31
6. Indoor unit accessories ........................................................................................................... 32
7. Selecting an installation site .................................................................................................... 33
7.1. Basic operation of the PAA unit .................................................................................... 33
8. Installation ............................................................................................................................. 34
8.1. Installation clearance ................................................................................................... 35
9. Duct connections ................................................................................................................... 37
10. Mount positions .................................................................................................................... 38
10.1. TH1 thermistor and NAT thermostat installation ........................................................... 38
10.2. Vertical/Downflow installation ..................................................................................... 39
10.3. Horizontal left installation ........................................................................................... 52
10.4. Horizontal right installation ......................................................................................... 59
11. Refrigerant piping work ......................................................................................................... 60
11.1. Insulation of refrigerant lines ....................................................................................... 63
11.2. Piping size ................................................................................................................ 63
12. Drain connections ................................................................................................................ 64
13. Float switch ......................................................................................................................... 67
14. Installing the control box ....................................................................................................... 71
14.1. Control box - cabinet installation ................................................................................. 72
14.2. Control box - external installation ................................................................................ 73
15. Electrical wiring .................................................................................................................... 75
15.1. Warning and caution .................................................................................................. 75
15.2. Connecting line voltage .............................................................................................. 76
15.3. Electrical settings ...................................................................................................... 77
15.4. PAA unit control box .................................................................................................. 79
15.5. Control signals to the furnace ..................................................................................... 83
15.6. PAA unit control options ............................................................................................. 84
15.6.1. MA remote controller ....................................................................................... 85
15.6.2. IT terminal connection options ......................................................................... 86
15.7. DIP switch for emergency thermostat .......................................................................... 88
15.8. Balance points .......................................................................................................... 91
15.8.1. Economic balance point .................................................................................. 91
15.8.2. Capacity balance point .................................................................................... 92
15.8.3. Extended balance point ................................................................................... 93
15.9. Condensate overflow safety switch connection (CN4F) ................................................ 93
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
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