AirComm Corporation Bell Air Conditioner206AB Installation Instructions TORQLOK PLUMBING

							  Page 10 of 21 
 206EC-250M 
 Rev E 
Fitting Torquing Procedures and Torque Values 
 
 
Insert O-Ring Fitting (Green O-Ring)     Torq-Lok Fitting (Black O-Ring) 
 
    Apply refrigerant oil to O-ring and female side of fitting. 
    Confirm there is no damage / nicks or dirt on fittings. 
    Slide B-nut back away from end of tube so you may see 
    O-ring as you slide the fitting together. 
 
 
 
     Be careful not to pinch O-ring. 
    Engage male end into female fitting being very careful to 
    maintain alignment and not pinch O-ring during this step. 
 
    The male flange should seat fully against the metal side 
    of the female flange without the O-ring being pinched. 
 
    Hold fitting together while siding B-nut forward and engaging threads. 
    Tighten B-nut, and torque to the following settings. 
 
    #6 Fittings: 30-35 in lbs     Do not over torque 
    #8 Fittings: 40-45 in lbs 
    #10 Fittings: 50-55 in lbs 
 
Once system is charged, check each fitting with an electronic leak detector. (an 
Electronic Leak Detector is the only reliable method of checking for refrigerant leaks). 
Once fittings have been checked and are leak free, Torque Seal as appropriate. 
 
System leak check 
 
Identification of and elimination of any system fitting leaks is extremely important to 
insure a trouble free system. 
 
A system which contains a partial charge can be leak tested and recharged without 
evacuating the system. The system can be pressurized with nitrogen or R134a 
refrigerant. A system which has been evacuated should be filled to a pressure of at 
least 50 psig of refrigerant or 150 psi nitrogen prior to the leak survey. 
  
						

							  Page 11 of 21 
 206EC-250M 
 Rev E 
 
System Leak Check (cont)  
 
The system should be leak tested using an electronic leak detector. Initial leak check can be 
accomplished with a refrigerant charge of .5 lbs and the electronic leak detector. Each fitting 
should be checked and repaired prior to the final charging process. 
Do not use compressed air for the pressure check! Compressed air can introduce moisture 
in the system which will cause it to operate poorly or not at all. Take your time, and check all 
around each fitting. A little extra time during the leak check will save a significant amount of time 
later  during servicing or troubleshooting. 
 
All leak checks should be conducted with the air conditioner “off”. Since the refrigerant is 
heavier than air, leaks are most likely detected on the underside of hoses and fittings. Also the 
refrigerant will collect in low areas and provide an erroneous leak indication. A stream of “shop 
air” through a nozzle is useful in clearing an area just before checking for leaks. 
 
If a leak is detected at an O-ring fitting, reclaim the system and install a new O-ring. Lubricate 
the O-ring with refrigerant oil prior to installation. 
 
A small amount of leakage (one once per year) past the compressor seal in normal. Most leak 
detectors are sensitive enough to show a leak of this magnitude. 
 
Charging Procedure 
NOTE 
This system should be serviced by qualified personnel only. 
 
1.  Leak check system in accordance with procedures present on pages 9 and 10. 
2.  Evacuate system for a minimum of 30 minutes. 
3.  Charge the system with 2.4 lbs (single fwd. Evaporator) or 2.6 lbs (Dual fwd. Evaporator) 
of R134a refrigerant. System pressures can very depending on temperature / humidity 
relationships. The most accurate method of charging a system is to add an initial 
refrigerant charge of 2.0 lbs then continue to add refrigerant until the evaporator outlet 
air temperature and system suction pressure reaches a minimum and subsequently 
starts to increase. When adding the refrigerant after the initial charge it should be done 
in increments of .25 lbs, and a minimum of 10 minutes allowed to elapse before adding 
each additional .25 lbs of refrigerant charge. This allows the system to stabilize and 
reach its maximum cooling potential for the given charge. The optimum charge occurs 
when evaporator outlet air temperatures are at their lowest. Any additional refrigerant will 
cause the outlet air temperature to increase and system performance to be degraded. 
Charge the system to the point of noticing the first temperature increase, then reduce 
charge back to the optimum point where outlet air temperatures were lowest. 
 
Refrigerant Pressure 
 
  System pressures will very due to temperature and humidity relationships. 
 
NOTE 
System overcharging, or operation of system during low ambient conditions may result 
in tailrotor pedal feedback. 
  
						

							  Page 12 of 21 
 206EC-250M 
 Rev E 
 
System troubleshooting 
 
Prior to troubleshooting a defective system, conduct a visual inspection for general 
condition. Inspect condenser fins for damage, comb out bent fins, and Check circuit 
breakers in baggage compartment. 
 
The following step-by-step procedures list the easiest checks, and most likely problem 
sources, first. 
 
1. Electrical 
 
With the engine off turn switch to “Blower” and make sure all evaporator blowers 
operate in both Hi and Low modes. Pull evaporator circuit breaker in battery 
compartment, and turn switch to A/C. Check that the condenser blower and 
actuator assy. Is working, and the compressor clutch is engaging. 
 
2. System Charge 
 
(See page 11, “Charging Procedures”) 
 
3. Expansion Valve Malfunction 
 
If the cooling loss is limited to only one evaporator, it is most likely a defective 
expansion valve. 
 
Loss of cooling in all evaporators (assuming that there were no problems 
identified during steps 1 or 2) could be caused by refrigerant flow blockage at the 
expansion valves. This blockage could be due to ice or dirt. 
 
Replacement of the drier bottle and a thorough system evacuation might be a fix 
(remove the possibility of ice at the expansion valve nozzles). 
 
4. Compressor Malfunction 
 
If the system will not maintain the pressures and there are no system leaks, the 
problem could be a failed compressor. The compressor must then be replaced. 
 
 
 
 
 
 
 
 
  
						

							  Page 13 of 21 
 206EC-250M 
 Rev E 
 
SYSTEM TROUBLESHOOTING TABLE 
 
Problem Cause Solution 
 
1. Premature Belt Failure  a.  Belt too loose 
b. Compressor misalign. 
c.  System over charged a.  Adjust belt tension 
b. Re-install/align 
compressor 
c.  Adjust system charge 
2. Condenser blower motor 
Circuit Breaker “Pops” a. Probable cause- 
Overheating of condenser 
blower motor a. Check for loose or rubbing 
of fan blade, or possible 
replacement of motor 
3. Water (Condensate) in area 
of the aft evaporator a.  Condensate drain fitting 
on evaporator not sealed 
b. Evaporator housing not 
sealed 
c.  Drain line / check valve 
not installed properly 
d.  Condensate forming on 
plumbing fittings a.b.c. Verify that installation 
conforms to drawing 
requirements. (remove 
evaporator inlet duct, and 
pour 1/2 ltr. of water into 
housing assy. To check for 
leaks & drainage. 
d. apply cork insulation to all 
exposed refrigerant lines. 
4. Water in chin bubble area 
of forward evaporator a. Forward evaporator 
housing not sealed 
b.  Condensate drain line 
fittings not secure at 
evaporator connection. 
c.  Drain line check valve not 
installed a. Same as problem #3 a.b.c. 
5. Conditioned air outlet 
louvers broken / loose  a. Replace Louvers 
6. Evaporator Coil freeze up  a. System suction pressure 
(temperature) too low. System 
suction pressure should not 
be below 20 psi. a. Adjust system charge to 25 
- 32 psi. 
7. System not Cooling  a.  Loss of refrigerant 
b.  Water in system a.  Evacuate system, leak 
check and recharge. 
b.  Evacuate system, replace 
receiver drier bottle, & 
recharge  
8.System with Poor Cooling  a. By-pass valve  a. Check to insure the 
temperature control knob 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. 
 
 
  
						

							  Page 14 of 21 
 206EC-250M 
 Rev E 
 
PERIODIC INSPECTIONS AND OVERHAUL SCHEDULE 
 
Item  Prior to  
Cooling  
Season Every 
100 hr. 
Operation Overhaul / 
Replacement 
Hours 
3 
 
    
Check Evap. Blower 
Operation Hi/Low X X  
    
Check Cond. Blower 
Operation X X  
    
Belt wear & Tension 
1 X X  
    
Condenser Fins  X  X   
    
Placards    
    
Compressor Mounting 
Lugs For Cracks X X  
    
Condenser Blower 
Motor - - On Condition 
 
Replace Belt 2      When evidence of excessive wear 
 
 
Notes: 
 
1   It is acceptable to remove the compressor drive belt during the cold weather season. 
Care should be taken to insure that the compressor is securely supported by the belt 
tension link. 
 
2 The belt tension on a newly installed belt should be reset after two hours of 
operation. 
 
3 The warranty period of the condenser blower motor is 1000 hours or 1 year 
whichever occurs first. It is acceptable to operate the condenser blower beyond the 
warranty period as no safety-of-flight issues are involved. Failure of the condenser 
blower will cause the system over-pressure switch to electrically shut the system off. 
You may elect to purchase a new condenser blower motor after 1000 hours of 
operation, or wait until the blower motor failure occurs. 
 
 
 
   
						

							  Page 15 of 21 
 206EC-250M 
 Rev E 
 
 
 
General Arran
gement – Air Conditioner S
ystem with sin
gle Forward Eva
porato
r  
						

							  Page 16 of 21 
 206EC-250M 
 Rev E 
 
 
 
General Arrangement – Air Conditioning System with Dual Forward Evaporator  
						

							  Page 17 of 21 
 206EC-250M 
 Rev E 
 
 
General Arrangement – Electrical Systems Components  
						

							  Page 18 of 21 
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 Rev E 
 
  
						

							  Page 19 of 21 
 206EC-250M 
 Rev E