Do you have a question about the TR-134 and is the answer not in the manual?
Questions and answers
Joe Garner
July 15, 2025
I have a Skylane 182T with a Keith a/c system. Belt driven compressor
Nothing works
No A/c
No fan only
No A/C indicator light
I’m thinking electrical problem???
Joe Garner
June 17, 2025
I have a Skylane 182T
I have a Keith A/C unit with belt driven compressor. Last summer had unit charged because was blowing warm air. Worked good for two weeks then nothing. No fan only either. Don’t know how to troubleshoot. It seems like I’ve lost power but don’t know if there’s a pressure switch that might have killed power?
Do you have an electric diagram for that system?
Thanks
Joe
Products, INC. TR-134 System Service Manual LIST OF EFFECTIVE PAGES SECTION PAGE DATE Title January 8, 2010 Record of Revisions January 8, 2010 January 8, 2010 List of Effective Pages January 8, 2010 Table of Contents January 8, 2010 Introduction...
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Products, INC. TR-134 System Service Manual TABLE OF CONTENTS SUBJECT PAGE Title Record of Revisions Table of Contents Introduction AIR CONDITIONING SYSTEM DESCRIPTION Vapor Cycle System Description Electrical Driven Compressor Systems Engine Driven Compressor Systems REFRIGERANT SERVICING General Discharging System...
Keith Products, INC. air conditioning systems using R134a refrigerant. It is intended to be used for all Keith Products air conditioning systems using R134a refrigerant that do not contain separate maintenance instructions. The System Service Manual supplements the Maintenance Manual supplied by Keith Products for your particular aircraft type.
Two R134a service valves are sized differently to avoid incorrect cross-connecting when gaining access to the plumbing for system recharging. The compressor on Keith Products air conditioning systems is driven either by an electrical motor, or by the engine. Listed below is a more detailed description of electric and engine driven compressor systems.
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Products, INC. TR-134 System Service Manual Figure 1. Air Conditioning Vapor Cycle System Sep 15/95 Page 3...
Products, INC. TR-134 System Service Manual 2. ELECTRICAL DRIVEN COMPRESSOR SYSTEMS Electrically operated systems use the aircraft electrical system and are operable in most normal flight modes. Air conditioning may be operated with ground external power or the aircraft electrical system providing voltage to the proper buss.
Products, INC. TR-134 System Service Manual 3. ENGINE DRIVEN COMPRESSOR SYSTEMS Engine driven systems use compressors that are engine mounted; or on some rotorcraft, driven off the tail rotor drive shaft. A pulley via a "V" type belt turns the compressor.
Products, INC. TR-134 System Service Manual 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.
Products, INC. TR-134 System Service Manual 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.
Products, INC. TR-134 System Service Manual 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.
Products, INC. TR-134 System Service Manual 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.
Products, INC. TR-134 System Service Manual 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. Remarks Keith Hose Coupler Tool...
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Products, INC. TR-134 System Service Manual 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.
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Products, INC. TR-134 System Service Manual 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.
Products, INC. TR-134 System Service Manual 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.
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.
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Products, INC. TR-134 System Service Manual 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: Hose should only be cut with a sharp knife.
Products, INC. TR-134 System Service Manual 4. COIL CLEANING MAINTENANCE PROCEDURES A. General The following procedure is used for cleaning either evaporator or condenser coil. B. Tools and Equipment Designation Ref. No. Remarks Vacuum Cleaner Comm. Avail. None Coil Cleaner Comm.
Products, INC. TR-134 System Service Manual 5. EXPANSION VALVE REMOVAL AND INSTALLATION A. General The following procedure is used to remove or install the air conditioning system expansion valve. B. Tools and Equipment Designation Ref. No. Remarks Sealant ES49000-1 None Polyolester Oil Comm.
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Products, INC. TR-134 System Service Manual (Figure A) (Figure B) (Figure C) Aug 21/06 Page 18...
Products, INC. TR-134 System Service Manual 6. COMPRESSOR MAINTENANCE PROCEDURES A. General The following procedure is used whenever the compressor is replaced or contamination is suspected. B. Tools and Equipment Designation Ref. No. Remarks None None C. Compressor Replacement Flush system and replace compressor per the Refrigerant Servicing section.
Products, INC. TR-134 System Service Manual TROUBLESHOOTING 1. GENERAL The procedures below present troubleshooting charts for the air conditioning system and the compressor. A diagnoses chart is presented for insufficient air conditioning system cooling. The performance characteristics of an aircraft's particular system is dependant upon the design parameters of the systems components.
Products, INC. TR-134 System Service Manual 3. AIR CONDITIONING SYSTEM TROUBLESHOOTING CONDITION SERVICE PROBABLE CAUSE CORRECTIVE PRESSURE ACTION GAUGE READING INSUFFICIENT SUCTION REFRIGERANT PRESSURE: below Refrigerant is low, or leaking 1. Leak test. CHARGE normal a little. 2. Repair leak.
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Products, INC. TR-134 System Service Manual CONDITION SERVICE PROBABLE CAUSE CORRECTIVE PRESSURE ACTION GAUGE READING AIR IN SYSTEM SUCTION PRESSURE: above Insufficient cooling. normal Air mixed with refrigerant in 1. Discharge system. system. 2 Replace receiver drier. Sight glass shows DISCHARGE 3.
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Products, INC. TR-134 System Service Manual SERVICE CORRECTIVE CONDITION PROBABLE CAUSE PRESSURE ACTION GAUGE READING FAULTY COMPRESSOR SUCTION Internal problem in 1. Discharge system. Insufficient cooling. PRESSURE: much compressor, or damaged 2. Remove and check above normal gasket and valve.
Products, INC. TR-134 System Service Manual 4. COMPRESSOR TROUBLESHOOTING A. General The following procedures are used for troubleshooting the compressor. Tools and Equipment Designation Ref. No. Remarks Service Pressure Gauge Comm. Avail. None DC Power Supply None C. Compressor Troubleshooting Procedures...
Products, Inc TR-134 System Service Manual CHECKS 1. GENERAL The following procedures are used to perform typical maintenance checks for air conditioning system refrigerant leaks, refrigerant charge and compressor oil level. CAUTION: Do not operate air conditioning system with condenser air outlet blocked.
Products, Inc TR-134 System Service Manual 3. REFRIGERANT SYSTEM LEAKAGE CHECK A. The system leakage check is to be performed in an area with an ambient temperature of 65°F or above. B. Install service pressure gage to low and high pressure R-134a service valves.
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Products, Inc TR-134 System Service Manual RESERVED January 8, 2010 Page 28...
Need help?
Do you have a question about the TR-134 and is the answer not in the manual?
Questions and answers
I have a Skylane 182T with a Keith a/c system. Belt driven compressor Nothing works No A/c No fan only No A/C indicator light I’m thinking electrical problem???
I have a Skylane 182T I have a Keith A/C unit with belt driven compressor. Last summer had unit charged because was blowing warm air. Worked good for two weeks then nothing. No fan only either. Don’t know how to troubleshoot. It seems like I’ve lost power but don’t know if there’s a pressure switch that might have killed power? Do you have an electric diagram for that system? Thanks Joe