AirComm Corporation Bell 412 Air Conditioner Instructions for Continued Airworthiness User Manual

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
Revision 14 Page 31 
 
 
(Removal & Replacement of the compressor drive belt guards) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 
10
:  COMPRESSOR DRIVE ILLUSTRATION
 
412EP & 412HP Drive Pulley
 
412 & 412SP Drive Pulley
 
412 
-3500 & 412
-3504 Drive Pulley Belt Guard Installation
 
NOTE:
 Use aft coupling bolts for shaft balance adjustment
 
  

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
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(Removal & Replacement of the speed reducer pulley) 
 
Figure 11:  COMPRESSOR DRIVE ILLUSTRATION 
X-X Direction   

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
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 (Removal & replacement of the speed reducer bearing) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Speed Reducer Pulley and Bearing Assembly
 
Figure 
12
:  COMPRESSOR DRIVE ILLUSTRATION
  

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
Revision 14 Page 34 
4. REMOVAL, INSTALLATION / REPLACEMENT OF AIR CONDITIONER 
COMPRESSOR ASSEMBLY 
 
 REMOVAL 
 
A. See Removal, Replacement, and Adjustment of Compressor Drive Belt (pages 27-30) 
 prior to the removal of the air conditioner compressor assembly, following Steps A-D 
 under the Removal section. 
B. It will be necessary to evacuate (discharge) the refrigerant from the system to remove 
 and replace the air conditioner compressor. Instructions...

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
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5. REMOVAL, INSTALLATION / REPLACEMENT OF THE AIR CONDITIONER 
COMPRESSOR DRIVE PULLEY FROM THE MAIN TRANSMISSION DRIVE SHAFT 
 
 REMOVAL 
 
A. See Removal, Replacement & Adjustment of Compressor Drive Belt (Page 27 and 28) 
 prior to the removal of the air conditioner drive shaft pulley. 
B. It should be noted that the air conditioner drive pulley is a two-piece assembly, and the 
 main transmission drive shaft need not be removed. It is...

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
Revision 14 Page 36 
B. Reconnect the ducting that attaches the forward evaporator to the forward blower 
 assemblies. 
 
CAUTION 
Refrigerant servicing should be performed by qualified personnel only. 
 (Removal & Replacement of the forward evaporator(s) assembly continued) 
 
CAUTION 
Always use a backup wrench when removing or installing refrigerant line fittings. 
 
C. Reconnect the refrigerant lines that attach closest to the evaporator assembly.   
D....

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
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 INSTALLATION / REPLACEMENT 
 
A. Install the aft evaporator assembly in the evaporator housing. 
B. Reconnect the drain tube to the bottom of the aft section of the aft evaporator housing. 
C. Reconnect the wires to the aft evaporator blower motors on the aft side of the evaporator 
 assembly. 
D. Reinstall the five (5) mounting bolts that attach the aft evaporator assembly to the cabin 
 roof. 
CAUTION 
Refrigerant servicing should be...

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
Revision 14 Page 38 
 
 INSTALLATION / REPLACEMENT 
 
A. Install the condenser assembly. 
B. Reinstall the eight (8) mounting bolts in the condenser assembly support legs. 
 
CAUTION 
Always use a backup wrench when removing or installing refrigerant lines. 
 
CAUTION 
Refrigerant servicing should be performed by qualified personnel only. 
 
C. Reinstall the refrigerant lines that connect closest to the condenser assembly. 
D. Reconnect the electrical...

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
Revision 14 Page 39 
 
 INSTALLATION / REPLACEMENT 
 
NOTE 
Never reuse a receiver drier bottle, and keep new receiver drier bottles capped until just prior to 
their installation. 
 
A. Install the receiver drier bottle. 
B. Tighten the retaining clamp holding the receiver drier bottle to the support bracket. 
 
 CAUTION 
Refrigerant servicing should be performed by qualified personnel only. 
 
CAUTION 
Always use a backup wrench when removing or installing...

AIR CONDITIONER SERVICE MANUAL 412AC-208M 
 
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11. REMOVAL, INSTALLATION / REPLACEMENT OF THE BY-PASS VALVE 
ASSEMBLY 
 
 REMOVAL 
 
A. Remove the forward transmission cowling to gain access to the by-pass valve assembly, 
 which is located on the aft side of the condenser assembly. 
B. It will be necessary to evacuate (discharge) the refrigerant from the system to remove or 
 replace the by-pass valve. Instructions for servicing the system are found in Chapter 6 
 Servicing....