AirComm Corporation Bell Air Conditioner206AB Installation Instructions TORQLOK PLUMBING

							 
 
 
 
 
 
 
AIR COMM CORPORATION 
Boulder Municipal Airport 
3300 Airport Rd. 
Boulder, CO.  80301 
 
 
 
 
 
 
 
 
 
Document No. 206EC-250M 
 
 
 
 
 
 
 
 
 
MAINTENANCE INSTRUCTIONS 
BELL 206 A/B AIR CONDITIONER SYSTEM 
For System Installation 
206EC-201 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
REV E  8 September 2011  
						

							  Page 1 of 21 
 206EC-250M 
 Rev E 
 
Revisions 
 
 Rev  Date   Description    Appl 
  
 A  03/07/05  
Pg. 5- added Fasco motor to list.      
            Revised Pgs 17 and 18 to include both the    
      ES61060-2 (Panasonic motor) and the  
      ES61142-1 motor (Fasco) 
 
 
B   09/22/05  Part number ES61060-2 blower motor replaced 
            With part number ES61064-1. Page 5 of 20. 
 
C    12/27/2007                  Part number ES57008-2 Replaced by      
                                                            part number ES57178-1. Pages 4 of  
                                                            20, 5 of 20, 17 of 20 and 18  
        of 20              
 
  D    10/7/08    Part number ES26112-4 Replaced by  
      part number ES26194-4. Pages I, 1 of 20,  
      5 of 20, and 19 of 20.  RM  
 
E    9/8/11     Changed Overhaul / Replacement schedule 
criteria. Page 14 of 21. 
           RL 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
						

							  Page 2 of 21 
 206EC-250M 
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Table of Contents 
 
Introduction           3 
 
Reference Documents         3 
 
System Description and Operation       4 
 
Suggested Spares List         5 
 
Safety Procedures          6 
 
Tools, Equipment, and Consumables       7 
 
Lubrication           8 
 
Receiver Drier Bottle         8 
 
Refrigerant Fittings          8 
 
Belt Replacement and Adjustment        9 
 
Fitting Torquing Procedures        10 
 
System Leak Check          10 
 
System Charging          11 
 
System Troubleshooting          12 
 
Periodic Inspections and Overhaul Schedule      14 
 
Drawings: 
 
General Arrangement         15-16 
Electrical System          17 
Electrical Schematic         18-20 
Drive Pulley Installation         21 
 
 
 
 
 
 
  
						

							  Page 3 of 21 
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Introduction 
 
This document provides maintenance and service information for the ACC 206EC-201 
Cabin Air Conditioning system installation in the Bell 206 A/B Helicopter. 
 
The drawings which are listed below are considered to be part of this document. 
 
Reference Documents 
 
1.  Dwg 206EC-201 General Arrangement  - 206 A/B Air Conditioner system 
(Torq-Lok). 
 
2.  Dwg 206EC-304 Compressor Installation. 
 
3.  Dwg 206EC-548 Plumbing Installation. 
 
4.  Dwg 206EC-646 Single Forward Evaporator Installation. (L/H Primary) 
 
5.  Dwg 206EC-648 Dual Forward Evaporator Installation. 
 
6.  Dwg 206EC-628 Aft Evaporator Installation. 
 
7.  Dwg 206EC-682 Air Distribution System.  
 
8.  Dwg 206EC-728 Condenser Installation. 
 
9.  Dwg 206EC-854 Electrical Installation. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
						

							  Page 4 of 21 
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System Description and Operation 
 
The 206EC-201 system is a vapor cycle type Air Conditioner consisting of a 
Compressor, Condenser, Dryer, By-pass valve, and Multiple Evaporator assemblies. 
 
The Compressor is belt driven off of the tail rotor drive shaft, which is located in the 
engine compartment. 
 
The Condenser assembly is located below the baggage compartment floor. Cooling air 
is forced through the condenser by a 28V DC electric blower, and an electrically 
actuated scoop that opens and closes when the system is switched from OFF to ON to 
OFF. 
 
Each evaporator assembly contains a 28V DC, two speed electric blower that allows the 
system to be switched to ether a High or Low setting. 
 
A refrigerant gas by-pass valve is located aft of the baggage compartment. The purpose 
of this valve, is to prevent evaporator heat exchanger freeze-up by controlling the 
minimum evaporator pressure (temperature).  
 
The system incorporates a binary high/low pressure “cut-out’ switch. This switch is 
intended to protect the compressor in case of system over-pressure or loss of 
refrigerant. The switch is located adjacent to the system charging ports ( Aft of the 
baggage door on the L/H side of the aircraft) and is wired in series with the compressor 
clutch. 
 
Switch operating pressures:  Low Pressure function – 
     Open @ 28 ± 2.8 psi 
     Close @ 29 ± 4.3 psi  
 
     High Pressure function – 
     Open @ 384 ± 30 psi 
     Close @ 298 ± 43 psi 
 
 
 
 
 
 
 
 
 
 
 
  
						

							  Page 5 of 21 
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Suggested Spares List 
 
 
  Item       Part Number 
 
 
Forward Evaporator Blower Motor    ES61064-10 
 
Aft Evaporator Blower Motor     ES61142-1 
 
Condenser Blower       ES73186-1 
 
Compressor        S-3008EC-6 
 
Compressor Drive Belt      7255 
 
Relay – Control       W389DCX-3 
 
Relay – Evaporator       W389CX-8 
 
Relay – Condenser       W389CX-13 
 
Receiver Drier Bottle      ES43034-1 
 
Binary Hi/Lo Pressure Switch     ES57178-1 
 
Circuit Breaker (1 Amp)      MS26574-1  
 
Circuit Breaker (5 Amp)      MS26574-5 
 
Circuit Breaker (15 Amp)      MS26574-15 
 
Circuit Breaker (20 Amp)      MS26574-20 
 
Resistor – Fwd Evaporator      ES63003-1 
 
Resistor Plate Assy. – Aft Evaporator    S-6104EC-1 
 
Bypass Valve       ES26194-4 
 
 
 
 
 
  
						

							  Page 6 of 21 
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Safety Precautions 
 
The refrigerant used in the air conditioning system is HFC R134a. This refrigerant is 
non-explosive, non-flammable, non-corrosive, has practically no odor, and is heavier 
than air. Although R134a is classified as a safe refrigerant, certain precautions must be 
observed to protect parts involved and the person(s) working on the system. 
 
Liquid R134a at normal atmospheric pressure and temperature evaporates so quickly 
that it will freeze anything that it contacts. Care must be taken to prevent any liquid 
refrigerant from coming in contact with the skin, especially the eyes. R134a is readily 
absorbed by most types of oil, therefore it is recommended a bottle of clean mineral oil 
and weak solution of boric acid be kept nearby when servicing the refrigerant system. 
 
 
 
 
CAUTION 
 
 
Always wear safety goggles when servicing any part of the refrigerant system. Should 
any liquid refrigerant get into the eyes, use a few drops of mineral oil to wash them out, 
then use a weak solution of boric acid to wash eyes, and seek aid from a doctor 
immediately even though the irritation has ceased. 
 
It is important to keep the system tightly sealed because the refrigerant system is 
always under pressure. Heat applied to any part of the system will cause the pressure 
to build up excessively. 
 
 
 
CAUTION 
 
 
To avoid explosion, never weld, use a flame-type leak detector, blow torch, solder, stem 
clean, bake on aircraft finish, or use excess amounts of heat on, or in the immediate 
area of any part of the air conditioning system or refrigerant supply tank, while they are 
closed to the atmosphere. 
 
 
 
 
 
 
 
  
						

							  Page 7 of 21 
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Tools, Equipment, and Consumables 
 
 
1.  Service Equipment: (Suggested) 
Recovery / Recycling / Recharging Station- 
 
Robinair Model 34700 or Equivalent 
Montpelier, OH 
1-800-822-5561 
 
2. Electronic Leak Detector: (Suggested) 
 
Micron – Tech III or Equivalent 
Model 209907 
Murray (NAPA) 
 
3. O-ring:  
 
CAUTION 
 
This system is charged with R134a 
Refrigerant and must be fitted with 
HSN O-rings (green in color) 
 
3. Lubricant: 
 
CAUTION 
 
This system is charged with R134a 
 Polyester Refrigerant Oil. 
DO NOT USE OTHER 
LUBRICANTS. Source: ICI America, 
Wilmington, DE. (1-800-822-8215) 
 
4. Refrigerant: 
 
DuPont HFC R134a 
 
 
 
 
 
 
 
  
						

							  Page 8 of 21 
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Lubrication 
 
The total air conditioning system oil charge is 7.5 + .5 oz. The compressors are factory 
charged with 3.5 oz. of oil. An additional 4 oz. of oil should be added to the discharge 
line prior to system charging. 
 
Care should be taken to avoid spilling any of the compressor oil charge during 
installation. If this should occur, drain the oil and recharge the 3.5 oz. 
 
The oil charge is continuously circulated by the refrigerant while the system is operating. 
If the system charge is reclaimed, of if a sudden loss of refrigerant occurs, a significant 
amount of oil will be removed from the system. An attempt must be made to determine 
the amount of lost oil. Generally, the amount lost is approximately 4 oz., this amount 
should be added for sudden loss of refrigerant. If reclaiming refrigerant, check the 
amount of oil removed from the system by the reclaiming machine and replace when 
recharging. 
 
CAUTION 
 
Inadequate oil or refrigerant in the system can result in compressor 
“Lock-Up” and require replacement of the compressor. 
 
Receiver Drier Bottle 
 
The receiver drier is the system reservoir and is located adjacent to the charging ports. 
The drier bottle contains a desiccant filter (silica gel) which serves to absorb moisture 
from the system. 
 
NOTE 
 
To prelude saturation of the desiccant, the drier line caps should not be removed 
until just prior to evacuation and charging of the system. The drier bottle should 
be replaced when ever the system is suspected of being contaminated with 
moisture. 
 
Refrigerant Fitting Assembly Instructions 
 
A light coat of refrigerant oil should be applied to all O-rings prior to assembly. 
 
O-ring fittings should be tightened sufficiently to slightly compress the O-ring (Excessive 
Torque Will Damage the Fitting). See O-ring installation instructions on the following 
page. 
 
 
  
						

							  Page 9 of 21 
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Belt Replacement and Adjustment 
 
To replace the compressor drive belt it is necessary to remove the tail rotor drive shaft 
segment between the engine transmission and the air conditioner drive pulley. (see 
BHT Service Manual). 
 
Proper belt tension in important to insure a long belt service life and to avoid excessive 
side load on the tailrotor driveshaft bearing. 
 
The proper belt tension is achieved as shown below: 
 
                                               P = 3 lbs.      Belt Tension = 49 lbs 
 
 
 
 
    Approximate 
    Belt deflection = .1” 
 
 
Add force of 3 lbs to midpoint of belt span. Belt with correct tension should deflect .1 
inch at the midpoint of belt span. 
 
NOTE 
 
RESET BELT TENSION AFTER TWO HOURS OF OPERATION OF NEW BELT.