Mitsubishi Electric PAA-A18AA1 Manuel D'installation page 2

Table of Contents
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1 ................................................................................................. 6
1. Warning .................................................................................................................................. 6
2. System introduction and dimensions ........................................................................................ 7
2.1. System introduction ...................................................................................................... 7
2.2. Dimensions .................................................................................................................. 9
3. Inspect shipment .................................................................................................................... 11
4. Disclaimer ............................................................................................................................. 12
5. Safety precautions ................................................................................................................. 13
5.1. Before installation and electric work .............................................................................. 13
5.2. Devices that use R410A refrigerant .............................................................................. 21
5.3. Before getting started .................................................................................................. 22
5.4. Before getting PAA unit installed (moved) - electrical work ............................................. 27
5.5. Before starting the test run ........................................................................................... 29
5.6. After installation and test run ........................................................................................ 30
5.7. To dispose the PAA unit ............................................................................................... 30
6. Indoor unit accessories ........................................................................................................... 31
7. Selecting an installation site .................................................................................................... 32
7.1. Basic operation of the PAA unit .................................................................................... 32
8. Installation ............................................................................................................................. 33
8.1. Installation clearance ................................................................................................... 33
9. Duct connections ................................................................................................................... 35
10. Mount positions .................................................................................................................... 36
10.1. TH1 thermistor and NAT thermostat installation ........................................................... 36
10.2. Upflow/Downflow installation ...................................................................................... 38
10.3. Horizontal left installation ........................................................................................... 50
10.4. Horizontal right installation ......................................................................................... 57
11. Refrigerant piping work ......................................................................................................... 58
11.1. Insulation of refrigerant lines ....................................................................................... 61
11.2. Piping size ................................................................................................................ 61
12. Drain connections ................................................................................................................ 62
13. Float switch ......................................................................................................................... 65
14. Installing the control box ....................................................................................................... 69
14.1. Control box - cabinet installation ................................................................................. 70
14.2. Control box - external installation ................................................................................ 72
15. Electrical wiring .................................................................................................................... 73
15.1. Warning and caution .................................................................................................. 73
15.2. Connecting line voltage .............................................................................................. 74
15.3. Electrical settings ...................................................................................................... 76
15.4. PAA unit control box .................................................................................................. 77
15.5. Control signals to the furnace ..................................................................................... 80
15.6. PAA unit control options ............................................................................................. 81
15.6.1. MA remote controller ....................................................................................... 82
15.6.2. IT terminal connection options ......................................................................... 83
15.7. DIP switch for emergency thermostat .......................................................................... 85
15.8. Balance points .......................................................................................................... 88
15.8.1. Economic balance point .................................................................................. 88
15.8.2. Capacity balance point .................................................................................... 89
15.8.3. Extended balance point ................................................................................... 90
15.9. Condensate overflow safety switch connection (CN4F) ................................................ 90
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
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