Air Conditioner System ICA Supplement

Transcription

1 Cessna Aircraft Company Page i Report No.: ICA-525B CESSNA AIRCRAFT COMPANY AIRCRAFT DIVISION WICHITA, KANSAS MODEL NO: 525B REPORT NO: ICA-525B REPORT DATE: 3/6/08 PREPARED BY: CHECKED BY: APPROVED BY: APPROVED BY:

2 Cessna Aircraft Company Page ii REVISIONS Rev Date By Approved By - See Title Page See Title Page See Title Page ECR Section ALL Description Initial Release

3 Cessna Aircraft Company Page iii CONTENTS Section / Title Page REVISIONS... II CONTENTS... iii FIGURES... V TABLES... V 1.0. INTRODUCTION Purpose APPLICABILITY Effectivity Complete ICA Documents DESCRIPTION AND OPERATION Description Operation System Component(s) FWD EVAP DUCT TEMP SENSOR ASSY CONDENSER MODULE-BRUSHLESS CKPT COLD AIR DUCT INSTL EVAPORATOR INSULATION Aircraft Wiring Interior Wiring REMOVAL AND INSTALLATION FWD EVAP DUCT Removal Installation TEMP SENSOR ASSY Removal Installation CONDENSER MODULE-BRUSHLESS Removal Installation... 7

4 Cessna Aircraft Company Page iv CKPT COLD AIR DUCT INSTL Removal Installation EVAPORATOR INSULATION Removal Installation MAINTENANCE AND SPECIAL TOOLS Maintenance Condenser Blower Assembly disassembly procedures: Condenser Blower Assembly cleaning procedures: Condenser Blower Assembly procedures: Assembly of Condenser Blower System Wiring TESTING, RETURN TO SERVICE, AND REPAIR Adjustment/Test Inspection/Check Repair AIRWORTHINESS LIMITATIONS Limitations and Replacement Intervals Mandatory replacement times Mandatory inspection intervals Mandatory inspection procedures

5 Cessna Aircraft Company FIGURES Page v Figure / Title Page FIGURE Forward Evaporator Duct...3 FIGURE Temperature Sensor Assembly...4 FIGURE Cockpit Cold Air Duct Routing...5 FIGURE Condenser Blower Assembly...12 TABLES Table / Title Page TABLE Installation ICA Effectivity...2 TABLE Temperature Sensor Assembly...4 TABLE Cockpit Cold Air Duct Routing...5 TABLE Standard Torque Values...11 TABLE Condenser Blower Assembly...13 TABLE Inspection Schedule...15

6 Cessna Aircraft Company Page 1 Report No.: ICA-525B INTRODUCTION 1.1. Purpose The purpose of this Instructions for Continued Airworthiness Supplement is to provide the maintenance technician with the information necessary to ensure the correct functionality and performance of the Air Conditioner System on the Cessna Model 525B This supplemental document is designed to satisfy the required 14 CFR Instructions for Continued Airworthiness requirements associated with this installation. This document is a supplement to the Model 525B Maintenance Manual and may or may not be incorporated If this information is incorporated into the Model 525B Maintenance Manual, the maintenance manual shall take precedence over this supplemental document. Refer to the applicable ATA chapter and section of the respective Maintenance Manual for the status of all ICA Supplements applicable to your model. NOTE: This document must be placed with the aircraft operator s Technical Library CD- ROM or Maintenance Manual and incorporated into the operator s scheduled maintenance program.

7 Cessna Aircraft Company Page ICA 2.0. APPLICABILITY 2.1. Effectivity This Instructions for Continued Airworthiness (ICA) supplement is effective for the following aircraft model(s) and serialization where this Air Conditioner System/Change is installed: Beginning Ending Model Effectivity Effectivity 525B TABLE Installation ICA Effectivity 2.2. Complete ICA Documents The following document(s), in conjunction with this supplement, constitute the Instructions for Continued Airworthiness for the Air Conditioner System system. All items must be available to the operator at initial delivery. Air Conditioner System Installation Manual Model 525B Wiring Diagram Manual Model 525B Interior Maintenance Manual 525B , where is the serial effectivity of the aircraft. Model 525B Illustrated Parts List Model 525B Maintenance Manual

8 Cessna Aircraft Company Page ICA 3.0. DESCRIPTION AND OPERATION 3.1. Description To improve system performance, numerous steps have been taken. The aft temperature sensor was oriented to a position more directly in the airflow. This allows for a more precise evaluation of cabin temperature. Insulation was added under the aft evaporator to isolate the sensor from cold under floorboard air. Improved cockpit distribution was accomplished by routing the pilots armrest Wemac directly from the forward evaporator Operation 3.3. System Component(s) FWD EVAP DUCT The duct is installed instead of NH and closely resembles this duct with one significant difference. The duct has a small divergent duct leading to the pilot armrest Wemac and it is located under the Forward Evaporator. (Refer to Figure 3.3-1) FIGURE Forward Evaporator Duct

9 Cessna Aircraft Company Page TEMP SENSOR ASSY The assembly has increased the angle of the aft evaporator cover pulling the temperature sensor away from the evaporator. And is located in front of the aft evaporator. (Refer to Figure 3.3-2) FIGURE Temperature Sensor Assembly FIGURE ITEM PART NUMBER NOMENCLATURE UNITS ASSY BRACKET ASSY BRACKET ASSY COVER SENSOR SUPPORT SENSOR TEMP 1 6 A850 THERMISTOR 1 TABLE Temperature Sensor Assembly CONDENSER MODULE-BRUSHLESS The Condenser Module is replacing the brushed condenser. It is located in the tail cone. This change will remove the 1000 hour brush inspection for the condenser.

10 Cessna Aircraft Company Page CKPT COLD AIR DUCT INSTL The cockpit duct installation is used in place of the This provides the ducting to connect the duct to the pilot Wemac. (Refer to Figure 3.3-3) FIGURE Cockpit Cold Air Duct Routing PART NUMBER NOMENCLATURE 1 BWT FLEXIBLE DUCT ASSY 1 2 BWT FLEXIBLE DUCT ASSY 1 3 BWT FLEXIBLE DUCT ASSY 2 4 MS STRAP DUCT INSULATION TORSO AIR ADAPTER ASSY 2 FIGURE ITEM UNITS ASSY TABLE Cockpit Cold Air Duct Routing

11 Cessna Aircraft Company Page EVAPORATOR INSULATION The insulation is installed under the aft evaporator. This is installed to hinder the flow of under floor air over the temperature sensor allowing for a more accurate cabin reading Aircraft Wiring Interior Wiring Refer to the Interior Maintenance Manual 525B , where is the aircraft serial effectivity, for cabin wiring and wire routing. 4.0

12 Cessna Aircraft Company Page REMOVAL AND INSTALLATION NOTE: If applicable, make sure that the aircraft is configured for maintenance as defined by the associated system in the maintenance manual or in this document, including the removal of electrical power, avionics power, hydraulic power, etc., prior to removal or installation of aircraft components FWD EVAP DUCT Removal No Change from NH removal process. (Model 525B Maintenance Manual, Section , R134a Air Conditioner System-Maintenance Practices) Installation No Change from NH installation process. (Model 525B Maintenance Manual, Section , R134a Air Conditioner System-Maintenance Practices) TEMP SENSOR ASSY Removal No Change from removal process. (Model 525B Maintenance Manual, Section , Temperature Control-Maintenance Practices) Installation No Change from installation process. (Model 525B Maintenance Manual, Section , Temperature Control-Maintenance Practices) CONDENSER MODULE-BRUSHLESS Removal No Change from removal process. (Model 525B Maintenance Manual, Section , R134a Air Conditioner System-Maintenance Practices) Installation No Change from installation process. (Model 525B Maintenance Manual, Section , R134a Air Conditioner System-Maintenance Practices)

13 Cessna Aircraft Company Page CKPT COLD AIR DUCT INSTL Removal To remove , cut strap attaching pilot Wemac duct to Duct. Then remove ducting as outlined in Maintenance Manual. (Model 525B Maintenance Manual, Section , Air Distribution System-Maintenance Practices) Installation When installing duct use new MS Strap to attach pilot Wemac duct to Duct. (Model 525B Maintenance Manual, Section , Air Distribution System-Maintenance Practices) EVAPORATOR INSULATION Removal To remove insulation cut the adhesive and remove insulation Installation When installing duct place insulation under aft evaporator and use Type II class A RTV sealant around outside edge of insulation. 5.0 ICA

14 Cessna Aircraft Company Page MAINTENANCE AND SPECIAL TOOLS 5.1. Maintenance Condenser Blower Assembly disassembly procedures (Refer to Figure 5.2-1): Removal of Condenser Blower (Vane Axial Blower), (70) Disconnect power leads to motor Remove the 6 cap mounting screws (80,90) that secure the housing of the blower to the shroud. NOTE: Note direction of blower airflow before removing the condenser assembly. CAUTION: TAKE EXTREME CARE NOT TO DAMAGE BLOWER HOUSING OR FAN BLADES WHILE REMOVING COMPONENT FROM ASSEMBLY Remove vane axial blower from shroud. A putty knife or similar tool may be needed to cut RTV between blower and shroud Lift vane axial blower out of condenser assembly Removal of Shroud Assembly (30) Remove condenser blower per Remove shroud mounting hardware (40,50,60). CAUTION: TAKE CARE TO PREVENT DAMAGE TO THE SHROUD ASSEMBLY AND COIL WHILE SEPERATING AND CUTTING RTV Use a putty knife and cut RTV along shroud and coil mounting surface areas to free shroud from coil Condenser Blower Assembly cleaning procedures: The following components of the Condenser Blower Assembly will require periodic cleaning (refer to the Inspection Schedule in section 6 for time intervals). This is not an all encompassing list. If at any time during the inspection process a component is found to be dirty, use a soft cloth to remove all contaminants from external surfaces (Refer to Figure 5.2-1). Vane Axial Blower (70) Shroud Assembly (30) Condenser Coil Assembly (20)

15 Cessna Aircraft Company Page 10 CAUTION: USE EXTREME CARE WHEN HANDLING FAN. DO NOT DROP OR APPLY EXCESSIVE LOADS TO BLADE SURFACES OR FAN IMBALANCE MAY RESLUT VANE AXIAL BLOWER ASSEMBLY: Over time, the vane axial blower assembly will become dirty and require general cleaning. It is essential that the assembly remain clean to ensure proper operation and optimal performance. Gain access to vane axial blower assembly (refer to the aircraft maintenance manual for removal of access panels and other hardware that might need to be removed). Use soft cloth, a soft utility brush and/or vacuum, or other suitable cleaning tools, and remove any dirt, dust, or other foreign matter SHROUD ASSEMBLY: Over time, the shroud assembly may show signs of separating and/or cracking and this can cause the condenser blower assembly to have less than optimal performance. Gain access to shroud assembly (refer to the aircraft maintenance manual for removal of access panels and other hardware that might need to be removed). If there are signs of separation between the shroud and the condenser assembly, the shroud must be removed and reinstalled using new RTV, Type II Class A (Refer to Disassembly, section 5.1.1, and Assembly, Section 5.1.3). Once the shroud is removed, clean the separated areas carefully with isopropyl alcohol to remove any dirt, dust, and other foreign matter, to include the old RTV sealant. Refer to Repair (section 6.3) for resealing procedures. If there are signs of cracking, the shroud should be removed and replaced (Refer to Disassembly section and Assembly section 5.1.3) Condenser Blower Assembly procedures (refer to Figure ): Assembly of Shroud Assembly (30) Ensure that shroud assembly and coil assembly mounting surface areas are thoroughly clean and free of any dirt or other foreign matter (refer to Cleaning, Section 5.1.2) Apply a thin bead of RTV sealant, Type II Class A, on the shroud mounting surface and install, insuring correct orientation (refer to Repair, Section 6.3). CAUTION: DO NOT OVER TORQUE SCREWS, OR DAMAGE TO THE SHROUD AND COIL MAY RESULT.

16 Cessna Aircraft Company Page Install mounting hardware (40,50,60) (refer to table for torque specifications) Assembly of Condenser Blower (70) Apply a small bead of RTV sealant, Type II Class A, on the condenser shroud and install the vane axial blower insuring the orientation of the wires are correctly positioned Install all mounting screws and washers (80, 90) and torque (refer to Standard Torque Values, Table 5.1-1) Rotate blower wheel to ensure there is no rubbing and that the blower outlet is free of all foreign matter and obstructions Connect motor wiring, then connect power leads to condenser blower and perform functional test per Testing and Fault Isolation, Section 3.2. TYPE FASTENER DESCRIPTION/LOCATION TORQUE SET SCREW ALL LOCATIONS IN-LBS 6-32 SCREW ALL LOCATIONS 8-10 IN-LBS 8-32 SCREW ALL LOCATIONS IN-LBS SCREW ALL LOCATIONS IN-LBS ¼-28-UNF ALL LOCATIONS IN-LBS 5/16-24UNF ALL LOCATIONS IN-LBS 3/8-24UNF ALL LOCATIONS IN-LBS 3/8 PLUMBING CONNECTIONS RECEIVER DRYER INLET PORT IN-LBS ½ PLUMBING CONNECTIONS COMPRESSOR DISCHARGE PORT IN-LBS ½ PLUMBING CONNECTIONS COIL HEADERS IN-LBS TABLE Standard Torque Values 5.2. System Wiring 6.0 REFER TO THE WIRING DIAGRAM MANUAL, CHAPTER 20, STANDARD PRACTICES, FOR WIRING MAINTENANCE REQUIREMENTS AND PRACTICES.

17 Cessna Aircraft Company Page 12 FIGURE Condenser Blower Assembly

18 Cessna Aircraft Company Page 13 A FIG. ENVIRO UNITS ITEM PART NUMBER NOMENCLATURE ASSY CONDENSER ASSEMBLY 20 **CONDENSER COIL ASSEMBLY N/P **SHROUD ASSEMBLY 1 40 AN960-10L **WASHER FLAT Z **LOCKNUT X500IH **SCREW (PURCHASE 10-32X1/2IH) X375IH **SCREW (PURCHASE 10-32X3/8IHW) **FAN VANE AXIAL 1 80 NAS **WASHER FLAT 6 90 NAS P **SCREW CAP 6 TABLE Condenser Blower Assembly

19 Cessna Aircraft Company Page TESTING, RETURN TO SERVICE, AND REPAIR 6.1. Adjustment/Test Condenser Blower Assembly testing procedures: Ensure that power is applied to the aircraft and that the air conditioning system is switched on using the cockpit mounted selector switch. Gain access to Condenser Blower Assembly (refer to the aircraft maintenance manual for removal of access panels and other hardware that might need to be removed). Verify that it is operating and perform the following: Verify that system is running smoothly and that there is no excessive noise and/or vibration coming from the assembly. Verify that the system is cooling properly If there is excessive noise and/or vibration coming from the condenser blower assembly or the system is not cooling, refer to the Disassembly procedures in section 5.1 and check inspection procedures in section 6.2. This will help in identifying whether one or more components are dirty or damaged and are in need of repair or replacement Inspection/Check R-134a Air Conditioning System Component Inspection Schedule Condenser Blower Assembly inspection schedule: If any component listed in this schedule requires cleaning, refer to Cleaning Procedure (Section 5.1.2) If any component listed in this schedule requires repair and/or replacement, refer to Repair (Section 6.3).

20 Cessna Aircraft Company Page 15 Component Type Inspection Service Hours Condenser outlet and Visually inspect condenser outlet and fan shroud for signs of cracking, 800 fan shrouds separation between shroud and condenser coil. Condenser coil Visually inspect condenser coil for damage or dirt accumulation. 800 Visually inspect, clean and comb coil fins. Inspect for leakage. Inspect plumbing for damage weathering and wear Visually inspect return bends for nicks, dents, cracks, or other damage Repair TABLE Inspection Schedule Condenser Blower Assembly repair procedures The following components may require periodic repair and/or replacement (refer to the Inspection Schedule in Section 6.2 for mandatory time intervals) (refer to Figure 5.2-1): Vane Axial Blower Assembly (70) Shroud Assembly(30) Condenser Coil Assembly (20) VANE AXIAL BLOWER ASSEMBLY: The vane axial blower motor and fan assembly is a balanced assembly and cannot be removed and replaced in the field. If there is damage to this assembly in any way, remove the entire vane axial blower assembly (refer to Disassembly, Section and Assembly, Section 5.1.3) and return to Enviro Systems for repair or replacement. Contact Enviro System customer service.

21 Cessna Aircraft Company Page SHROUD ASSEMBLY: The shroud assembly can, over time, show signs of cracking and separation between the shroud and the condenser coil assembly. This can cause the condenser blower assembly to have less than optimal performance. If the shroud is separating, refer to Disassembly (Section 5.1.1) for removal of shroud. Then refer to Cleaning (Section 5.1.2). After insuring that the seam between the shroud and condenser has been cleaned according to the cleaning procedures (Section 5.1.2), apply a new bead of RTV, Type II Class A, and reinstall shrouds (refer to Assembly, Section 5.1.3). Allow RTV to cure for a minimum of 24 hours before operating system. If the shrouds are cracked or are damaged in any other way, the shrouds should be replaced (refer to Disassembly, Section and Assembly, Section 5.1.3). Contact Enviro Systems customer service to order new components CONDENSER COIL ASSEMBLY: The condenser coil fins can, over time, become clogged with dirt, dust, and other foreign matter. The component can also become damaged. The coil return bends can, over time, become dented, cracked, or can start leaking. It is essential that the condenser coil as well as the coil bends remain clear and undamaged for proper operation of the condenser blower assembly. Refer to Cleaning (Section 5.1.2) for proper cleaning procedures. If coil fins are bent, use a fin comb and try straightening the fins. If fins and coil return bends are excessively damaged, the entire condenser blower assembly must be removed (refer to Disassembly, Section and Assembly, Section 5.1.3) and sent to Enviro Systems for repair. Contact Enviro Systems customer service to order new components. 7.0 ICA

22 Cessna Aircraft Company Page AIRWORTHINESS LIMITATIONS 7.1. Limitations and Replacement Intervals Cessna Aircraft Company Model 525B Maintenance Manual, Chapter 4, Airworthiness Limitations for Citation contains the system and airframe limitations for the Model 525B. NOTE: The Airworthiness Limitations section is FAA-approved and specifies maintenance required under Section and of the Code of Federal Regulations, unless an alternative program has been FAA approved. This system has no mandatory replacement time, inspection interval, or structural inspection procedures, and has no impact on Cessna Aircraft Company Model 525B Maintenance Manual, Chapter 4 Airworthiness Limitations for Citations or Model 208 or Chapter 5, Time Limits/Maintenance Checks for propeller airplanes Mandatory replacement times. NONE Mandatory inspection intervals. NONE Mandatory inspection procedures. NONE