AirComm Corporation Air Conditioner R134A Service Manual

							Products, INC. 
TR-134 System Service Manual
 
 
Aug 21/06 
Page 6 
 
 REFRIGERANT SERVICING 
 
1. GENERAL 
 
The air conditioning system uses refrigerant R134a and the compressor lubricating 
oil used is Polyolester Oil viscosity grade (ISO) 68.  No other refrigerant or 
compressor oil should be used. 
 
Refrigerant R134a 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 personnel and property when working 
with R134a refrigerant. 
 
WARNING:   
 
A.  Liquid R134a, at normal atmospheric pressure and temperature, evaporates so 
quickly that it tends to freeze anything that it contacts.  Care must be taken to 
prevent any liquid refrigerant from coming into contact with skin. 
 
B.  Always wear safety goggles when servicing any part of the refrigerant system 
to prevent refrigerant from coming into contact with the eyes. 
 
C.  To avoid explosion, never weld, use a blow torch, solder, steam clean, or use 
excessive amounts of heat on, or in, the immediate area of the air conditioning 
system, or refrigerant supply tank, full or empty, while they are closed to 
atmosphere. 
 
D.  The refrigerant service cart/container has a safe strength.  However, if handled 
incorrectly, it will explode.  Therefore, always follow the instruction on the label.  
In particular, never store it in a hot location (above 126°F, 52°C) or drop it. 
 
CAUTION:  Do not operate air conditioning system with condenser air outlet blocked. 
  
						

							Products, INC. 
TR-134 System Service Manual
 
 
Aug 21/06 
Page 7 
 
2. DISCHARGING SYSTEM 
 
A. General 
 
The air conditioning system refrigerant must be discharged prior to 
disconnecting or removing components in the refrigerant loop.  Federal law 
prohibits discharging refrigerant into the atmosphere.  Use only an R134a 
compatible recycling/recovery unit when discharging the air conditioning 
system. 
 
 
B. Tools and Equipment 
 
 
Designation  
Ref. No.  
Qty  
Remarks 
 
 
Service Pressure Gauge  
Comm. Avail.  
1  
None 
 
R134a Compatible 
Recycling/Recovery Unit  
Comm. Avail.  
1  
None 
 
 
C. Discharging Procedure 
 
1)  Connect R134a compatible recycling/recovery unit to the R134a service 
valves on the aircrafts air conditioning system.  If recovery unit does not 
have pressure gauges, connect service pressure to air conditioning system. 
 
2)  After cart oil level has been verified, evacuate the system, per recovery 
unit’s instructions.  Let the system sit for approximately 5-10 minutes to let 
any residual refrigerant boil from the system oil. Note the amount of post 
recovery oil in cart.  The amount of oil in the cart prior to recovery should be 
subtracted from the amount of oil after recovery. This is the amount of oil 
that needs to be added to the system before charging. 
 
3)  Remove recovery unit when discharging is complete. 
  
						

							Products, INC. 
TR-134 System Service Manual
 
 
Aug 21/06 
Page 8 
 
3. EVACUATING SYSTEM 
 
A. General 
 
The air conditioning system must be evacuated prior to charging the system 
with refrigerant.  Evacuating the system removes any moisture that may be in 
the system.  Use only an R134a compatible recycling/recovery unit when 
evacuating the air conditioning system. 
 
 
B. Tools and Equipment 
 
 
Designation  
Ref. No.  
Qty  
Remarks 
 
 
Service Pressure Gauge  
Comm. Avail.  
1  
None 
 
R134a Compatible 
Recycling/Recovery Unit  
Comm. Avail.  
1  
None 
 
 
C. Evacuating Procedure 
 
1)  Connect R134a compatible recycling/recovery unit to the R134a service 
valves on the aircrafts air conditioning system.  If recovery unit does not 
have pressure gauges, connect service pressure to air conditioning system. 
 
2)  Evacuate the air conditioning system in accordance with the recovery units 
instructions for a minimum of 15 minutes. 
 
3)  Once the air conditioning system has been evacuated, it is then ready for 
charging with new/recycled R134a refrigerant. 
  
						

							Products, INC. 
TR-134 System Service Manual
 
 
Aug 21/06 
Page 9 
 
4. CHARGING SYSTEM 
 
A. General 
 
Use only R134a refrigerant when charging air conditioning system.  Federal law 
prohibits discharging refrigerant into the atmosphere.  Use only R134a 
compatible recycling/recovery unit when charging the air conditioning system. 
 
 
B. Tools and Equipment 
 
 
Designation  
Ref. No.  
Qty  
Remarks 
 
 
Service Pressure Gauge  
Comm. Avail.  
1  
None 
 
R134a Compatible 
Recycling/Recovery Unit  
Comm. Avail.  
1  
None 
 
Polyolester Oil  
Comm. Avail  
A/R  
Viscosity ISO 68 
 
 
C. Charging Procedure 
 
1)  Connect R134a compatible recycling/recovery unit to the R134a service 
valves on the aircrafts air conditioning system.  If recovery unit does not 
have pressure gauges, connect service pressure to air conditioning 
system. 
 
2)  Add the amount of compressor oil recovered during discharging.  Add new 
polyolester oil, viscosity ISO 68 to the compressor oil fill port. 
 
3)  Charge the air conditioning system in accordance recovery unit’s 
instructions, until the sight glass just clears of bubbles.  This can also be 
accomplished by first initially charging the system with 1.5 lbs of refrigerant 
and then VERY slowly, with the system operating, introduce small amounts 
of refrigerant in .1 lb increments until the sight glass is clear of bubbles. 
 
NOTE:  Keep the low side closed and the high side open during charging so 
that liquid R134a passes through the evaporator and evaporates into a 
gas before entering the compressor.  Liquid R134a entering the 
compressor can cause permanent damage!  
						

							Products, INC. 
TR-134 System Service Manual
 
 
January 8, 2010 
Page 10 
 
5. FLUSHING SYSTEM 
 
A. General 
 
The following procedure is used to whenever the compressor is replaced and 
when system contamination is suspected. 
 
B. Tools and Equipment 
Designation Ref. No. Qty 
Remarks 
Keith Hose Coupler Tool See Procedures  A/R  None 
Service Pressure Gauge  Comm. Avail.  1  None 
R134a Compatible 
Recycling/Recovery Unit Comm. Avail.  1  None 
Polyolester Oil  Comm. Avail.  A/R  Viscosity ISO 68 
 
1.  System Flushing Procedure 
 
1.  Connect the refrigerant recovery cart to the normal service ports. 
 
2.  Empty the refrigerant recovery cart’s oil collection tube so that it begins with 
zero oil collected. 
 
3.  Discharge the air-conditioning system and recover the refrigerant per the 
refrigerant cart’s instructions.  Do not empty the oil collection tube. 
 
4.  Disconnect the refrigerant recovery cart from the normal service ports. 
 
5.  Remove the compressor and connect the service valve couplers to the 
suction and discharge plumbing hoses. 
 
•  O-ring Style Coupler P/N’s JBS6020-7 and JBS6020-8. 
•  Flare Style Coupler P/N’s JBS6020-9 and JBS6020-10.  
 
6.  Bypass the binary pressure switch.  If located on the condenser assembly, 
attach the plumbing hose directly to the condenser.  If located on the 
compressor then bypass per previous step. 
 
7.  Remove the receiver/drier bottle from the aircraft and properly dispose.  
Attach the hose coupler tool in place of the receiver/drier bottle.  
 
•  O-ring Style Coupler P/N JBS6009-1. 
•  Flare Style Coupler P/N JBS6020-6.  
						

							Products, INC. 
TR-134 System Service Manual
 
 
January 8, 2010 
Page 11 
 
 
8.  Disconnect all of the expansion valves from the evaporator assemblies.  
Attach the hose coupler tool in place of the expansion valves on all 
evaporator assemblies.  Use caution in handling the expansion valves.  Do 
no support the expansion valve by its remote bulb tubing.  Do not disconnect 
the external equalization port fitting if the expansion valve is an externally 
equalized style (ES26105-1 and ES26106-1). 
 
•  O-ring Style Coupler P/N JBS6020-3 
•  Flare Style Coupler P/N JBS6020-4 
 
9.  Connect the refrigerant recovery cart to the service port couplers located 
where the compressor was removed to create a refrigerant loop with the 
refrigerant cart. 
 
10.  Evacuate the system thru the HIGH side port only per the refrigerant 
recovery cart’s instructions for a minimum 10 minutes. 
 
11.  Charge the system thru the LOW side port only with 1.5 to 2 times a normal 
refrigerant charge of refrigerant.  Do not add any oil to system. 
 
12.  Recover the system thru the HIGH side port only per the refrigerant recovery 
cart’s instructions. 
 
13.  Repeat previous three steps two additional times. 
 
14.  Disconnect the refrigerant recovery cart from the service ports. 
 
15.  Remove the compressor and drain all of the oil from the compressor into an 
empty graduated cylinder.  It will be necessary to rotate the clutch plate 
several times to get as much oil as possible from the compressor. 
 
16.  Empty the refrigerant recovery cart’s oil collection tube into the graduated 
cylinder with the drained compressor oil.  Inspect the oil for debris 
contamination and replace compressor if necessary. 
 
17.  New compressors come serviced with 5 ounces of oil and do not require oil 
adjustment.  If the existing removed compressor is reused or other 
replacement compressor for which the oil level is unknown, then completely 
drain the compressor and then add 5 ounces of new polyolester oil ISO 
grade 68 to the compressor.  Torque the oil plug to 6 to 9 ft-lbs. 
 
18.  Install the compressor.  Use new o-rings. 
  
						

							Products, INC. 
TR-134 System Service Manual
 
 
January 8, 2010 
Page 12 
 
19.  Inspect the expansion valves for damage and debris.  Replace if any 
contamination is found.  Use new o-rings. 
 
20.  Inspect the binary pressure switch for damage and debris.  Flush with dry 
nitrogen or clean dry compressed air before re-installing.  Use new o-rings. 
 
21.  Install a new receiver/drier bottle.  Do not reuse the old bottle under any 
circumstance.  Use new o-rings. 
 
Caution:   Receiver/drier bottles left open to the atmosphere for more than 
10 minutes must be discarded and replaced with new. 
 
22.  Evacuate the system per the refrigerant recovery cart’s instructions for a 
minimum 15 minutes. 
 
23.  Add 1 ounces of new polyolester oil ISO grade 68 for each 7 feet of plumbing 
over 15 feet total length to the system thru the HIGH side port only. 
 
24.  Charge the system per Charging Procedure.  
						

							Products, INC. 
TR-134 System Service Manual
 
 
Aug 21/06 
Page 13 
 
 
 
GENERAL SERVICING
 
 
1. GENERAL 
 
General service procedures are provided to keep the air conditioning system 
operating at peak efficiency.  Procedures are provided for general maintenance 
tips, inspection intervals, maintenance of the plumbing system, to repair hoses, 
and to clean coils.  Procedures are also provided for removal and installation of the 
expansion valve. 
 
CAUTION:  Do not operate air conditioning system with condenser air outlet blocked. 
 
2. INSPECTION INTERVALS 
 
A. General 
 
Periodic inspections of the air conditioning system will keep the system 
operating at peak efficiency.   The inspections are simple visual inspections 
requiring a minimal amount of time.  
 
B. Inspection Intervals 
 
 
ITEM  
INSPECT FOR  
INTERVAL  
ACTION 
 
Air Conditioning 
System 
Components  
Dirt , Damage  
*Every 500 hours 
and annualy  
Clean or replace 
component as 
necessary 
 
Compressor Belt  
Tension, Wear  
Within 5 hours of 
installing new belt 
*Every 500 hours 
and annualy  
Tension or replace 
as necessary 
 
Sight Glass  
Proper refrigerant 
level  
When problem is 
suspected  
Discharge/charge as 
necessary per 
Refrigerant Servicing 
section 
 
Evaporator and 
condenser coils  
Dirt  
*Every 500 hours 
and annualy  
Clean as necessary 
 
*Recommended inspection interval maximums.  Actual inspection times should be 
conducted around the aircrafts existing regularly scheduled maintenance checks. 
  
						

							Products, INC. 
TR-134 System Service Manual
 
 
Aug 21/06 
Page 14 
 
3.  PLUMBING SYSTEM MAINTENANCE PROCEDURES 
 
A. General 
 
The following procedures are used to perform typical maintenance on the air 
conditioning system plumbing.  Procedures are provided for hose or fitting 
replacement.  New Keith Products air conditioning systems use swaged hose 
fittings.  Some systems that have been converted from R12 to R134a 
refrigerant use Barb Lok hose fittings.  Fittings are either o-ring type or use 
flared connections. 
 
B. Tools and Equipment 
 
 
Designation  
Ref. No.  
Qty  
Remarks 
 
 
R134a Compatible Hose Swaging 
Kit  
Available from 
Keith Products  
1  
None 
 
Sharp Knife  
Comm. Avail.  
1  
None 
 
Impact Wrench  
Comm. Avail.  
1  
None 
 
Light Machine Oil  
Comm. Avail.  
A/R  
None 
 
Polyolester Oil  
Comm. Avail.  
A/R  
Viscosity ISO 68 
 
Sealant  
ES49000-1  
A/R  
None 
 
C.  Hose or Fitting Replacement (Swaged Hose Fittings) 
    
NOTE:  If it is found that a hose or fitting has a leak, it will be necessary to replace 
the entire hose assembly.  Follow the Hose Swaging Instruction below: 
 
1.  Hose should only be cut with a sharp knife.  (Note:  Use of serrated 
blades or saws to cut hose will leave particles that can contaminate 
system.) 
2.  Insert the proper size die in the swaging tool. 
3.  Insert fitting in swaging tool so that it is centered in the die and hand 
tighten. 
4.  Insert hose in fitting until it bottoms (Note:  Indicating hole is in base of 
fitting). 
5.  Using impact wrench, tighten nut until die housings contact.  (Note:  It is 
important to keep hose pushed into fitting while swaging). 
6.  Reverse impact and back off nut until housing contacts rubber stops. 
  
						

							Products, INC. 
TR-134 System Service Manual
 
 
January 8, 2010 
Page 15 
 
D.  Hose or Fitting Replacement (Barb-Lok Hose Fittings) 
 
NOTE:  If it is found that a hose or fitting has a leak, it will be necessary to replace 
the entire hose assembly.  Follow the Hose Barb-Lok Instruction below: 
 
1.  Hose should only be cut with a sharp knife.  (Note:  Use of serrated 
blades or saws to cut hose will leave particles that can contaminate 
system.) 
2.  Slide the Barb-Lok socket onto the hose fitting with the round end towards 
the stop.  Apply a few drops of machine oil to nut to ease installation.  
(Note:  Do not lubricate fitting barbs.) 
3.  Push hose on barbed end of fitting until all barbs are covered.  Hose end 
shall be about 1/8 inch past last barb. 
4.  Hold hose in place.  Pull socket towards hose and thread onto hose 
counter-clockwise. Use wrench to turn socket onto hose.  The round end 
of the socket should be 0.82 inch (or one socket length) from the push-on 
hose stop. 
5.  About 1/8 inch of hose should protrude past the socket.  This may be 
trimmed to improve the appearance of the hose assembly. 
 
E.  Connection to Components - O-Ring Replacement 
 1.  Place the appropriate o-ring over the tube O end of the fitting.   
2.  Lubricate o-ring with polyolester oil or sealant prior to assembly. 
3.  Apply sealant to all fitting mating surfaces prior to assembly. 
 
  F.  Recommended standard dry torque specifications. 
 
O-Ring Flare Thread Size 
FT-Lb N-M FT-Lb N-M 
5/8”  11-13 15-18 20-25 27-34 
3/4  15-20 20-27 35-40 47-54 
7/8”  21-27 29-37 50-60 68-81 
1 1/16” 28-33 38-45 70-80 95-108 
 
G.  Connection to Components - Flared Fittings 
1.  Apply sealant to all fitting mating surfaces prior to assembly. 
 
H. Receiver/Drier Replacement 
1.  Replace receiver/drier whenever the compressor is replaced or when the 
air conditioning system plumbing is left open to the atmosphere for a 
period of time greater than 10 minutes.