Cessna Aircraft Company Page i Report No.: ICA-525B-21-00001 CESSNA AIRCRAFT COMPANY AIRCRAFT DIVISION WICHITA, KANSAS 67277 MODEL NO: 525B REPORT NO: ICA-525B-21-00001 REPORT DATE: 3/6/08 PREPARED BY: CHECKED BY: APPROVED BY: APPROVED BY:
Cessna Aircraft Company Page ii REVISIONS Rev Date By Approved By - See Title Page See Title Page See Title Page ECR 061758 Section ALL Description Initial Release
Cessna Aircraft Company Page iii CONTENTS Section / Title Page REVISIONS... II CONTENTS... iii FIGURES... V TABLES... V 1.0. INTRODUCTION... 1 1.1. Purpose... 1 2.0. APPLICABILITY... 2 2.1. Effectivity... 2 2.2. Complete ICA Documents... 2 3.0. DESCRIPTION AND OPERATION... 3 3.1. Description... 3 3.2. Operation... 3 3.3. System Component(s)... 3 3.3.1. 6314462-14 FWD EVAP DUCT... 3 3.3.2. 6314540-5 TEMP SENSOR ASSY... 4 3.3.3. 9912660-3 CONDENSER MODULE-BRUSHLESS... 4 3.3.4. 4717051-6 CKPT COLD AIR DUCT INSTL... 5 3.3.5. 6314540-11 EVAPORATOR INSULATION... 6 3.4. Aircraft Wiring... 6 3.4.1. Interior Wiring... 6 4.0. REMOVAL AND INSTALLATION... 7 4.1. 6314462-14 FWD EVAP DUCT... 7 4.1.1. Removal... 7 4.1.2. Installation... 7 4.2. 6314540-5 TEMP SENSOR ASSY... 7 4.2.1. Removal... 7 4.2.2. Installation... 7 4.3. 9912660-3 CONDENSER MODULE-BRUSHLESS... 7 4.3.1. Removal... 7 4.3.2. Installation... 7
Cessna Aircraft Company Page iv 4.4. 4717051-6 CKPT COLD AIR DUCT INSTL... 8 4.4.1. Removal... 8 4.4.2. Installation... 8 4.5. 6314540-11 EVAPORATOR INSULATION... 8 4.5.1. Removal... 8 4.5.2. Installation... 8 5.0. MAINTENANCE AND SPECIAL TOOLS... 9 5.1. Maintenance... 9 5.1.1. Condenser Blower Assembly disassembly procedures:... 9 5.1.2. Condenser Blower Assembly cleaning procedures:... 9 5.1.3. Condenser Blower Assembly procedures:... 10 5.1.4. Assembly of Condenser Blower... 11 5.2. System Wiring... 11 6.0. TESTING, RETURN TO SERVICE, AND REPAIR... 14 6.1. Adjustment/Test... 14 6.2. Inspection/Check... 14 6.3. Repair... 15 7.0. AIRWORTHINESS LIMITATIONS... 17 7.1. Limitations and Replacement Intervals... 17 7.1.1. Mandatory replacement times.... 17 7.1.2. Mandatory inspection intervals.... 17 7.1.3. Mandatory inspection procedures.... 17
Cessna Aircraft Company FIGURES Page v Figure / Title Page FIGURE 3.3-1 Forward Evaporator Duct...3 FIGURE 3.3-2 Temperature Sensor Assembly...4 FIGURE 3.3-3 Cockpit Cold Air Duct Routing...5 FIGURE 5.2-1 Condenser Blower Assembly...12 TABLES Table / Title Page TABLE 2.2-1 Installation ICA Effectivity...2 TABLE 3.3-2 Temperature Sensor Assembly...4 TABLE 3.3-3 Cockpit Cold Air Duct Routing...5 TABLE 5.1-1 Standard Torque Values...11 TABLE 5.2-1 Condenser Blower Assembly...13 TABLE 6.2-1 Inspection Schedule...15
Cessna Aircraft Company Page 1 Report No.: ICA-525B-21-00001 1.0. INTRODUCTION 1.1. Purpose 1.1.1. 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. 1.1.2. This supplemental document is designed to satisfy the required 14 CFR 23.1529 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. 1.1.3. 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.
Cessna Aircraft Company Page 2 2.0 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 -000246-000246 TABLE 2.2-1 Installation ICA Effectivity 2.2. Complete ICA Documents 2.2.1. 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-000246, where 000246 is the serial effectivity of the aircraft. Model 525B Illustrated Parts List Model 525B Maintenance Manual
Cessna Aircraft Company Page 3 3.0 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. 3.2. Operation 3.3. System Component(s) 3.3.1. 6314462-14 FWD EVAP DUCT The 6314462-14 duct is installed instead of NH3000869-10 and closely resembles this duct with one significant difference. The 6314462-14 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) 6314462-14 FIGURE 3.3-1 Forward Evaporator Duct
Cessna Aircraft Company Page 4 3.3.2. 6314540-5 TEMP SENSOR ASSY The 6314540-5 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 3.3-2 Temperature Sensor Assembly FIGURE ITEM PART NUMBER NOMENCLATURE UNITS ASSY 1 6314540-6 BRACKET ASSY 1 2 6314540-7 BRACKET ASSY 1 3 6314540-10 COVER 1 4 6314540-12 SENSOR SUPPORT 1 5 9912085-3 SENSOR TEMP 1 6 A850 THERMISTOR 1 TABLE 3.3-1 Temperature Sensor Assembly 3.3.3. 9912660-3 CONDENSER MODULE-BRUSHLESS The 9912660-3 Condenser Module is replacing the 9912583-7 brushed condenser. It is located in the tail cone. This change will remove the 1000 hour brush inspection for the condenser.
Cessna Aircraft Company Page 5 3.3.4. 4717051-6 CKPT COLD AIR DUCT INSTL The 4717051-6 cockpit duct installation is used in place of the 4717051-1. This provides the ducting to connect the 6314462-14 duct to the pilot Wemac. (Refer to Figure 3.3-3) FIGURE 3.3-3 Cockpit Cold Air Duct Routing PART NUMBER NOMENCLATURE 1 BWT24516-3 FLEXIBLE DUCT ASSY 1 2 BWT24517-1 FLEXIBLE DUCT ASSY 1 3 BWT24518-1 FLEXIBLE DUCT ASSY 2 4 MS3367-7-9 STRAP 5 5 4717051-2 DUCT INSULATION 1 6 4717051-3 TORSO AIR ADAPTER ASSY 2 FIGURE ITEM UNITS ASSY TABLE 3.3-2 Cockpit Cold Air Duct Routing
Cessna Aircraft Company Page 6 3.3.5. 6314540-11 EVAPORATOR INSULATION The 6314540-11 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. 3.4. Aircraft Wiring 3.4.1. Interior Wiring Refer to the Interior Maintenance Manual 525B-000246, where 000246 is the aircraft serial effectivity, for cabin wiring and wire routing. 4.0
Cessna Aircraft Company Page 7 4.0. 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. 4.1. 6314462-14 FWD EVAP DUCT 4.1.1. Removal No Change from NH3000869-10 removal process. (Model 525B Maintenance Manual, Section 21-50-00, R134a Air Conditioner System-Maintenance Practices) 4.1.2. Installation No Change from NH3000869-10 installation process. (Model 525B Maintenance Manual, Section 21-50-00, R134a Air Conditioner System-Maintenance Practices) 4.2. 6314540-5 TEMP SENSOR ASSY 4.2.1. Removal No Change from 6314540-4 removal process. (Model 525B Maintenance Manual, Section 21-60-00, Temperature Control-Maintenance Practices) 4.2.2. Installation No Change from 6314540-4 installation process. (Model 525B Maintenance Manual, Section 21-60-00, Temperature Control-Maintenance Practices) 4.3. 9912660-3 CONDENSER MODULE-BRUSHLESS 4.3.1. Removal No Change from 9912583-7 removal process. (Model 525B Maintenance Manual, Section 21-50-00, R134a Air Conditioner System-Maintenance Practices) 4.3.2. Installation No Change from 9912583-7 installation process. (Model 525B Maintenance Manual, Section 21-50-00, R134a Air Conditioner System-Maintenance Practices)
Cessna Aircraft Company Page 8 4.4. 4717051-6 CKPT COLD AIR DUCT INSTL 4.4.1. Removal To remove 4717062-6, cut strap attaching pilot Wemac duct to 6314462-14 Duct. Then remove ducting as outlined in Maintenance Manual. (Model 525B Maintenance Manual, Section 21-20-00, Air Distribution System-Maintenance Practices) 4.4.2. Installation When installing duct use new MS3367-7-9 Strap to attach pilot Wemac duct to 6314462-14 Duct. (Model 525B Maintenance Manual, Section 21-20-00, Air Distribution System-Maintenance Practices) 4.5. 6314540-11 EVAPORATOR INSULATION 4.5.1. Removal To remove 6314540-11 insulation cut the adhesive and remove insulation. 4.5.2. 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
Cessna Aircraft Company Page 9 5.0. MAINTENANCE AND SPECIAL TOOLS 5.1. Maintenance 5.1.1. Condenser Blower Assembly disassembly procedures (Refer to Figure 5.2-1): 5.1.1.1. Removal of Condenser Blower (Vane Axial Blower), (70) 5.1.1.1.1. Disconnect power leads to motor. 5.1.1.1.2. 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. 5.1.1.1.3. Remove vane axial blower from shroud. A putty knife or similar tool may be needed to cut RTV between blower and shroud. 5.1.1.1.4. Lift vane axial blower out of condenser assembly. 5.1.1.2. Removal of Shroud Assembly (30) 5.1.1.2.1. Remove condenser blower per 5.1.1.1. 5.1.1.2.2. Remove shroud mounting hardware (40,50,60). CAUTION: TAKE CARE TO PREVENT DAMAGE TO THE SHROUD ASSEMBLY AND COIL WHILE SEPERATING AND CUTTING RTV. 5.1.1.2.3. Use a putty knife and cut RTV along shroud and coil mounting surface areas to free shroud from coil. 5.1.2. Condenser Blower Assembly cleaning procedures: 5.1.2.1. 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)
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. 5.1.2.2. 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. 5.1.2.3. 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 5.1.1 and Assembly section 5.1.3). 5.1.3. Condenser Blower Assembly procedures (refer to Figure 5.2-1 ): 5.1.3.1. Assembly of Shroud Assembly (30) 5.1.3.2. 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). 5.1.3.3. 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.
Cessna Aircraft Company Page 11 5.1.3.4. Install mounting hardware (40,50,60) (refer to table 5.1-1 for torque specifications). 5.1.4. Assembly of Condenser Blower (70) 5.1.4.1. 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. 5.1.4.2. Install all mounting screws and washers (80, 90) and torque (refer to Standard Torque Values, Table 5.1-1). 5.1.4.3. Rotate blower wheel to ensure there is no rubbing and that the blower outlet is free of all foreign matter and obstructions. 5.1.4.4. 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.25-28 SET SCREW ALL LOCATIONS 40-50 IN-LBS 6-32 SCREW ALL LOCATIONS 8-10 IN-LBS 8-32 SCREW ALL LOCATIONS 12-15 IN-LBS 10-32 SCREW ALL LOCATIONS 20-25 IN-LBS ¼-28-UNF ALL LOCATIONS 50-70 IN-LBS 5/16-24UNF ALL LOCATIONS 100-140 IN-LBS 3/8-24UNF ALL LOCATIONS 160-190 IN-LBS 3/8 PLUMBING CONNECTIONS RECEIVER DRYER INLET PORT 130-160 IN-LBS ½ PLUMBING CONNECTIONS COMPRESSOR DISCHARGE PORT 300-400 IN-LBS ½ PLUMBING CONNECTIONS COIL HEADERS 250-325 IN-LBS TABLE 5.1-1 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.
Cessna Aircraft Company Page 12 FIGURE 5.2-1 Condenser Blower Assembly
Cessna Aircraft Company Page 13 A FIG. ENVIRO UNITS ITEM PART NUMBER NOMENCLATURE ASSY. 1-10 1134620-5 CONDENSER ASSEMBLY 20 **CONDENSER COIL ASSEMBLY N/P 30 1134619-1 **SHROUD ASSEMBLY 1 40 AN960-10L **WASHER FLAT 8 50 409-1032Z **LOCKNUT 4 60 10-32X500IH **SCREW (PURCHASE 10-32X1/2IH) 4 65 10-32X375IH **SCREW (PURCHASE 10-32X3/8IHW) 4 70 1250435-10 **FAN VANE AXIAL 1 80 NAS620-10 **WASHER FLAT 6 90 NAS1351-3-10P **SCREW CAP 6 TABLE 5.2-1 Condenser Blower Assembly
Cessna Aircraft Company Page 14 6.0. TESTING, RETURN TO SERVICE, AND REPAIR 6.1. Adjustment/Test 6.1.1. Condenser Blower Assembly testing procedures: 6.1.1.1. 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. 6.1.1.2. 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. 6.2. Inspection/Check 6.2.1. R-134a Air Conditioning System Component Inspection Schedule 6.2.1.1. Condenser Blower Assembly inspection schedule: 6.2.1.1.1. If any component listed in this schedule requires cleaning, refer to Cleaning Procedure (Section 5.1.2). 6.2.1.1.2. If any component listed in this schedule requires repair and/or replacement, refer to Repair (Section 6.3).
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. 6.3. Repair TABLE 6.2-1 Inspection Schedule 6.3.1. Condenser Blower Assembly repair procedures 6.3.1.1. 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) 6.3.1.1.1. 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 5.1.1 and Assembly, Section 5.1.3) and return to Enviro Systems for repair or replacement. Contact Enviro System customer service.
Cessna Aircraft Company Page 16 6.3.1.1.2. 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 5.1.1 and Assembly, Section 5.1.3). Contact Enviro Systems customer service to order new components. 6.3.1.1.3. 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 5.1.1 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
Cessna Aircraft Company Page 17 7.0. 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 43.16 and 91.403 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. 7.1.1. Mandatory replacement times. NONE 7.1.2. Mandatory inspection intervals. NONE 7.1.3. Mandatory inspection procedures. NONE