AirComm Corporation Cabin Air Conditioner A119 Instructions for Continued Airworthiness User Manual

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 35 
8. Removal and Replacement of Condenser Vane Axial Blower Assembly 
(Figure 4-8) 
 
Removal 
 
a. Remove screws that attach condenser blower assembly to the lower contour of 
the belly panel. This will allow the blower assembly to pivot on the forward hinged 
support plate. 
b. Disconnect vane axial blower assembly Molex connector. 
c. Remove inlet duct and attaching hardware. 
d. Remove bolts on each side of blower mount plates and remove vane axial blower 
assembly. 
 
Replacement 
 
a. Install vane axial blower assembly and attaching hardware to blower mount 
plates. 
b. Install inlet duct and attaching hardware.  Seal inlet edge with RTV. 
c. Connect Molex connector and secure as needed. 
d. Swing condenser blower assembly up and install screws that attach assembly to 
lower contour of the belly panel. 
9. Removal and Replacement of Compressor Drive Belt 
(Figure 4-3) 
Removal 
 
a. Cut safety wire on compressor belt tensioning link and belt tensioning link jam 
nuts, and loosen respective jam nut(s). 
b. Loosen lower compressor pivot bolt on the compressor mount to allow freedom 
of movement of compressor. 
c. Adjust belt tensioning link to loosen drive belt. 
d. Remove bolts securing oil cooler shaft to rotor brake disk and flange to allow 
removal of drive belt from drive pulley. Remove drive belt. 
 
Replacement 
 
a. Install drive belt on compressor pulley and drive pulley. 
b. Install bolts securing oil cooler shaft to rotor brake disk and flange. Torque to 75-
95 in-lbs (8.47-10.73 Nm). 
c. Adjust drive belt tension according to adjustment procedure below. 
d. Tighten and torque lower compressor pivot bolt on the compressor mount to 110-
130 in-lbs (12.43-14.69 Nm). 
 
Adjustment 
NOTE 
Proper  static  belt  tension  is  necessary  to  insure  proper  belt  life  and  to 
avoid  excessive  side  load  on  the oil  cooler  shaft.  The  belt  tension  should 
be reset after several hours of operation. 
 
a. The proper belt tension is achieved by using the following procedure.  
						

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 36 
b. Apply 2.8 lbs (1.27 Kg) of force using a tension tester midpoint of belt span 
between the compressor pulley and the drive pulley. 
c. Deviation should be .188 inch. Adjust belt tensioning link as required. 
d. Safety wire compressor belt tensioning link and jam nuts. 
 
 
 
 
 
 
10. Removal and Replacement of Compressor Assembly 
(Figure 4-3) 
NOTE 
It will be necessary to evacuate (discharge) refrigerant from the system to 
remove  or  replace compressor assembly.  Instructions  for  servicing  are 
found in Chapter 6. 
 
Removal 
 
a. Cut safety wire on compressor belt tensioning link and belt tensioning link jam 
nuts, and loosen respective jam nut(s). 
b. Loosen lower compressor pivot bolt on the compressor mount to allow freedom 
of movement of compressor. 
c. Adjust belt tensioning link to loosen drive belt. Remove belt from compressor 
pulley. 
d. Remove nut and bolt from upper compressor mount for belt tensioning link 
assembly and safety strap. 
e. Disconnect  refrigerant  plumbing  from compressor fittings  once  refrigerant  is 
evacuated. Always  use  a  back-up  wrench. Cap  open  lines  to  prevent 
contamination. 
f. Remove pivot  bolt,  washer,  and  sleeve  on  lower  compressor  mount.  Remove 
compressor. 
 
Replacement 
NOTE 
Replacement  compressors  have  been  serviced  with  Polyester  refrigerant 
(Ester)  oil  for  use  in  R134a  systems.    There is  no  need  to  add  additional 
oil for replacements. 
 
a. Install compressor and  secure pivot  bolt,  washer,  and  sleeve  on  lower 
compressor mount. Do not tighten pivot bolt. 
b. Install belt on compressor pulley.   
						

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 37 
c. Replace all O-rings before connecting refrigerant plumbing to compressor fittings 
using  a  back-up  wrench. Torque  refrigerant  line connections  to  40–45  inch-lbs 
(4.6-5.1 Nm) for the #8 fitting and 50–55 in-lbs (5.7-6.3 Nm) for the #10 fitting. 
d. Install nut  and  bolt  from  upper compressor  mount  for  belt  tensioning  link 
assembly and safety strap. Torque bolt to 110-130 in-lbs. 
e. Perform belt adjustment according to procedure in paragraph 9. 
f. Tighten and torque lower compressor pivot bolt on the compressor mount to 110-
130 in-lbs (12.43-14.69 Nm). 
g. Service air conditioning system with refrigerant. 
 
11. Removal and Replacement of Receiver Drier Bottle  
(Figure 4-9) 
NOTE 
It will be necessary to evacuate (discharge) refrigerant from the system to 
remove  or  replace receiver  drier  bottle. Instructions  for  servicing  are 
found in Chapter 6. 
 
Removal 
 
a. Remove screws that attach condenser blower assembly to the lower contour of 
the belly panel. This will allow the condenser blower assembly to pivot on the 
forward hinged support plate. 
b. Remove lower aft fairing to gain access to receiver drier bottle. 
c. Disconnect refrigerant plumbing from receiver drier bottle fittings once refrigerant 
is  evacuated. Always  use  a  back-up  wrench. Cap  open  lines  to  prevent 
contamination. 
d. Remove attaching  hardware  to clamps  securing receiver  drier  bottle.  Remove 
receiver drier. 
 
Replacement 
CAUTION 
Replacement receiver drier bottles  are  capped  to  prevent  moisture 
contamination.    Receiver drier bottles  left  uncapped  and  open  for  more 
than 10 minutes must be discarded and replaced. 
 
a. Install receiver drier bottle and secure clamps with attaching hardware. 
b. Replace all O-rings before connecting refrigerant plumbing to receiver drier bottle 
fittings  using  a  back-up  wrench. Torque  refrigerant  line connections  to 30–35 
inch-lbs (3.4-4.0 Nm) for the #6 fittings. 
c. Install lower aft fairing and install screws that attach condenser blower assembly 
to the lower contour of the belly panel. 
d. Service air conditioning system with refrigerant. 
 
12. Removal and Replacement of Bypass Valve  
(Figure 4-10) 
NOTE 
It will be necessary to evacuate (discharge) refrigerant from the system to 
remove  or  replace bypass  valve.  Instructions  for  servicing  are  found  in 
Chapter 6.  
						

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 38 
Removal 
 
a. Disconnect refrigerant plumbing from bypass valve once refrigerant is evacuated. 
Always use a back-up wrench. Cap open lines to prevent contamination. 
b. Disconnect electrical wiring from bypass valve solenoid. 
c. Remove  attaching  hardware  to  mounting  brackets securing  bypass  valve. 
Remove bypass valve. 
 
Replacement 
 
a. Install bypass valve and secure to mounting brackets with attaching hardware. 
b. Replace  all  O-rings before  connecting  refrigerant  plumbing  to  bypass  valve 
fittings  using  a  back-up  wrench. Torque  refrigerant  line connections  to  30–35 
inch-lbs (3.4-4.0 Nm) for the #6 fittings. 
c. Connect electrical wiring to bypass valve solenoid. Secure wiring as needed. 
d. Service air conditioning system with refrigerant. 
 
13. Removal and Replacement of Binary Switch  
(Figure 4-10) 
 
Removal 
 
a. Disconnect electrical wiring from binary switch. 
b. Remove  attaching  hardware  to clamp securing binary  switch.  Remove binary 
switch by unscrewing from Schrader valve on tube assembly. 
 
Replacement 
 
e. Install binary switch and secure clamp with attaching hardware. 
f. Connect electrical wiring to binary switch. 
   
						

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 39 
CHAPTER 8 
TROUBLESHOOTING 
1. System Troubleshooting 
 
Prior to troubleshooting a defective system, it is advisable to conduct a visual 
inspection for general condition and obvious signs of damage or failure. 
 
The following matrix lists the easiest checks and the most likely problems. 
 
Problem Probable Cause Corrective Action 
System not Cooling 
 
(Evaporator blowers still operating) 
System is low or empty of 
refrigerant 
 
Evacuate the system, determine the 
origin of the refrigerant leak if 
applicable, and re-charge the system 
 Moisture or air in the system Evacuate the system, replace the 
receiver drier, and place the system 
under a vacuum for a minimum of 45 
minutes before recharging the system 
 Compressor If the compressor has failed, it must be 
replaced 
 Compressor drive belt If the compressor drive belt has failed it 
will need to be replaced 
 By-pass valve Check to insure the temperature control 
knob on the A/C control panel in the 
cockpit is in the full cold position, and 
the temperature control circuit breaker 
has not tripped. If the valve remains 
open (by-passing refrigerant) the valve 
will need replacement 
 Condenser blower motor / fan 
assembly. 
Check to insure the condenser blower 
motor/fan assembly are receiving 
power, and the circuit breakers have not 
tripped; if the blowers still do not 
function, they may have failed internally 
and must be replaced 
System not cooling 
 
(Evaporator blowers not operating) 
Air conditioner control circuit 
breaker tripped. 
Reset circuit breaker; if breaker will not 
reset, check for short in circuit 
 Forward or Aft evaporator blower 
circuit breaker tripped. 
Reset circuit breaker; if breaker will not 
reset, check for short in circuit. 
 
   
						

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 40 
Problem Probable Cause Corrective Action 
System not cooling 
(Evaporator blowers not operating) 
Forward and aft evaporator blower 
motor(s) 
Check for power to the motor(s), 
and for the free movement of the 
blower wheel; if the motor shaft 
does not turn smoothly the motor 
must be replaced 
Loss of cooling limited to one 
evaporator 
Expansion valve malfunction If cooling is lost in only one of the 
evaporators, and the blowers 
continue to function, it is most 
likely a blockage at the expansion 
valve orifice, this is most often 
caused by dirt in the system 
forming a blockage as the 
refrigerant passes through the 
valve; evacuating the system and 
changing the receiver drier should 
cure this problem; if the above 
actions do not resolve the problem, 
the evaporator assembly must be 
replaced 
External moisture (Condensate) in 
the area of forward / aft evaporator 
Leak in evaporator, or evaporator 
drainage system 
If water is noted in the area near 
the evaporators, this is normally 
caused by a loose, cracked, 
plugged, or disconnected drain line 
NOTE 
The drain line consists of a tube 
which extends from the lower 
surface of the evaporators through 
the outer contour of the helicopter 
(Contact Air Comm Corporation Service Department for current pricing and availability of 
replacement components and parts) 
  
						

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 41 
Figure 8-1 – Electrical Schematic (IDS Equipped Aircraft) 
 
 
 
*1 
*2 
*2= 12 ga. wire with S-6501EC-3 condenser blowers, 14 ga. wire with A119-7008-1 condenser blowers 
*1= 20A circuit breaker with S-6501EC-3 condenser blowers, 15A circuit breaker with A119-7008-1 condenser blowers   
						

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 42 
Figure 8-2 – Electrical Schematic (Non IDS Equipped Aircraft) 
 
 
*1 
*2 
*1= 20A circuit breaker with S-6501EC-3 condenser blowers, 15A circuit breaker with A119-7008-1 condenser blowers  
*2= 12 ga. wire with S-6501EC-3 condenser blowers, 14 ga. wire with A119-7008-1 condenser blowers  
						

							AIR CONDITIONER SERVICE MANUAL A119-206M-1 
Revision 12 Page 43 
APPENDIX A 
WEIGHT AND BALANCE INFORMATION 
 
Agusta A119 Air Conditioner System: 
Ref. Dwg. A119-212 
 
Weight Breakdown (Single Forward Evaporator Blower) 
English Units 
Item Wt. 
(lbs) 
X-Arm 
(in) 
X-M 
(in-lb) 
Y-Arm 
(in) 
Y-M 
(in-lb) 
 
Total 
A119-212 
Air conditioning 
System 
99.67 134.9 13,444.9 -1.88 -187.6 
 
Metric Units  
Item Wt. 
(kg) 
X-Arm 
(mm) 
X-M 
(kg-mm) 
Y-Arm 
(mm) 
Y-M 
(kg-mm) 
 
Total 
A119-212 
Air conditioning System 
45.30 3426 155227 -47.8 -2165 
 
Weight Breakdown (Dual Forward Evaporator Blowers) 
English Units 
Item Wt. 
(lbs) 
X-Arm 
(in) 
X-M 
(in-lb) 
Y-Arm 
(in) 
Y-M 
(in-lb) 
 
Total 
A119-212 
Air conditioning System 
105.8 129.2 13,669.4 -1.56 -165.5 
 
Metric Units  
Item Wt. 
(kg) 
X-Arm 
(mm) 
X-M 
(kg-mm) 
Y-Arm 
(mm) 
Y-M 
(kg-mm) 
 
Total 
A119-212 
Air conditioning System 
50.0 3257.6 156,241.2 -50.4 -1,891.7