Air Conditioning System CC 350

Transcription

1 Air Conditioning System CC 350 March 2013

2 Index Contents 1. Introduction 2. Spheros Warranty Terms 3. CC 350 Data Sheet 4. CC 350 System Components 4.1. System Components Picture 4.2. System Components Explanation 4.3. Ordering Spareparts - Equipment Identification 4.4. Modelnumber 4.5. Equipment Components 4.6. Refrigerant Circuit 4.7. Installation Drawing 5. Controller & Operating 5.1. Controller WG Controller WG Operating 5.3. Controller 5.4. Numeric Display Set-point 5.5. Reading the temperature Ventilation Mode 5.6. Automatic Control Mode 5.7. Refrigeration Compressor Fans 5.8. Pressure switch ICE sensor 5.9. Heating Auxiliary Heaters Air Refreshment Mode Operation without panel 6. Maintenance, Troubleshooting 6.1. Preventive Maintenance 6.2. Preventive Maintenance Frequency Schedule 6.3. Troubleshooting General 6.4. Troubleshooting Faults 6.5. Troubleshooting Failure Diagnosis Table 7. Technical Data Sheet Overview 8. Notes

3 1. Introduction Spheros develops its products with a view to offering passengers a comfortable environment, always seeking for the best condition of personal well-being. The equipment offers a design that provides seamless integration with the vehicle, facilitating its operation and maintenance. With optimized design, high-cooling capacity and low noise assured. This manual was developed for the purpose to present some important aspects of function, operation and maintenance, so as to get optimum performance out of the air conditioning equipment. The controls installed by Spheros, which are used by the driver, are duly illustrated and explained in this manual. It s important to read the manual before starting to operate the air conditioning equipment. Spheros maintains a network of authorized services providers with tools, equipment and a team of professionals trained to perform any type of maintenance within the quality standards. Thank you for choosing Spheros products. For questions please contact the nearest Spheros authorized services provider or contact the technical assistance department. To ensure that the equipment has a long, useful and trouble free life, it is essential that the operations and maintenance instructions described in this manual are followed and performed regularly. 3

4 2. Spheros Warranty Terms 1 - The warranty period starts with the day of installation of the goods and the initial registration of the vehicle in which the initial installation is made, respectively. The warranty period ends at the latest 24 months after delivery of goods. 2 - Should the equipment be installed by a third party, Spheros warrants only the product and not its installations. 3 - During the stipulated period, the warranty completely covers the workman-ship and spare parts used to repair defects duly identified as being premature failure of material and component defects used on its manufacturing. 4 - Only a technician from the Spheros authorized network of services is qualified to repair the defects covered under the warranty. 5 - The warranty approval is subject to the technical analysis of the defects shown in the components and operational conditions to which the equipment has been subjected. 6 - No claims will be accepted if the vehicle is still in use after the defect is found, even if there is lack of replacement parts, delay in transportation or any other such incident. 7 - The warranty of the components used in the assembly of Spheros equipment, which have their own technical assistance network, will be obtained from their own network by presenting the Spheros warranty certificate. Taking for example an alternator from the supplier Bosch, the request should be forwarded directly to the service network of Bosch. 8 - The warranty looses its validity: a) if the installation or use of the product is not in accordance with the Spheros technical recommendations. b) if the product suffers any damage by accident, force of nature, misuse or alterations and repairs performed by unauthorized personnel. c) if the warranty certificate and/or the serial number of the product are adulterated, overwritten or damaged. d) if defects or unsatisfactory performance are caused by the use of non-original spare parts and in disagreement with the technical specifications of Spheros. e) if no original warranty certificate can be presented. 9 - The warranty does not cover: a) the displacement of the bus for repairing the equipment. In case the customer requests to be attended in the same place where the product is operating, it will be up to the authorized service provider to decide whether the visit will be chargeable or not. b) the support of customers in cities that do not have authorized services providers. There the expenses for the displacement are the sole responsibility of the owner. c) lack of proper preventive maintenance, as described in the preventive maintenance item in this manual. d) parts that wear out naturally: bearings, belts, filters in general, lubricating oil, relays and fuses. e) losses or losses of profits caused by the grounding of the vehicle due to the equipment not functioning. 4

5 3. CC 350 Data Sheet March

6 3. CC 350 Data Sheet Technical Data CC 350 Max. cooling capacity (kw) * 32 Air flow evaporator (free-blowing, m³/h) 6300 Quantity of blowers 6 Max. outside temperature ( C) 60 Refrigerant (CFE-free) R-134a Quantity of refrigerant (kg) ** 8,5 Compressor (cm³) 560 / 655 Weight (roof top unit, kg) 152 Dimensions (L x B x H in mm) 4250 x 1360 x 210 * inside temperature 27 C, outside temperature 35 C ** The quantity of refrigerant gas can vary according to the application and installation 6

7 4. CC 350 System Components March

8 4.1. CC 350 System Components Picture

9 4.2. CC 350 System Components Explanation 1 10 No. Description No. Description 1 Fluid Refrigerant: Spheros products use only R134a refrigerant in order to protect the environment as its globally accepted standard. The refrigerant is used to cool down the passenger compartment by changing its state. 2 Air Circulation: The air, after being cooled in the evaporator is distributed inside of the bus through some ducts. 3 Condenser: Its main function is to dissipate the heat absorbed by the refrigerant throughout the system. In the condenser, the overheated refrigerant, change its gassy state into a liquid. 4 Condenser Fan: The condenser fans, as well as the compressor, will only be on when the air conditioner operates in cooling mode. The Conderser Fan helps to keep the condenser cool and protects it from overheating. 5 Filter Dryer: Used to retain some dross and/or humidity that might be in the system to avoid damaging or blocking the expansion valve. 6 Evaporator: In the evaporator the refrigerant fluid, now at low pressure, changes its state from liquid to gas, absorbing heat in this process from the internal environment of the bus. 7 Air Filter: The air return filter retains the dross suspended in the air so as to avoid the accumulation of waste in the evaporator coils. 8 Relay Plate: The relay plate receives the orders from the controller and turns on the condenser fans, evaporator blowers and the compressor according to the selected operation mode. 9 Air Refreshment: This permits the entry of outside air in order to increase the oxygen level and to expel unwanted odors and impurities from inside the vehicle. 10 Drains: These are used to conduct the condensate humidity in the evaporator coils from the evaporator tray to the outside of the vehicle.

10 4.2. CC 350 System Components Explanation No. Description No. Description 11 Controller: Installed on the bus dashboard, the controller enables the driver to choose the setpoint temperature and view the internal bus temperature, thereby giving the driver complete climate control inside the bus. Set-point is the value of the desired temperature inside of the vehicle. 12 Expansion Valve: The thermostatic expansion valve restricts the entry of the high-pressure refrigerant that is coming from the condenser and its function is to regulate the refrigerant flowing through the evaporator so as to maintain the pressure and temperature at the coil outlet. 13 Temperature Sensor: Sensor to measure the temperature and therefore providing important data to the control system for an optimized air conditioning performance. 14 Evaporator Blower: The evaporator blowers are on in both ventilation and cooling mode and can operate at two speeds. The speed control can be automatic or manual. The blowers blow the cold air into the passenger compartment. 15 Compressor: When it is functioning, the compressor draws the refrigerant from the evaporator at its gassy state at low pressure, compresses it by raising the pressure and temperature and discharges it into the condenser. 16 Pressure Switch: The pressure switch is an electrical device that monitors the working pressures of the air-conditioner. Whenever there is a change in the normal operational pressure the compressor will shut down immediately so to avoid breaking. Note: The working pressure is monitored continuously even when the air conditioner is off. 17 Clutch: The compressor is powered by the vehicle engine with a belt transmission power system and a magnetic clutch whenever the air conditioner is operating in cooling mode.

11 4.3. Ordering Spare Parts Equipment Identification It is extremely important when ordering spare parts and sending other correspondences, that the customer identifies the air conditioner model, mentioning serial number, model and manufacturing date. This information may be found on the air conditioner s warranty certificate and on the identification tag. On this tag you will also find listed the refrigerant gas to be used and the necessary quantity for the model. Information regarding the application such as: body serial number and model, chassis serial number and model are also important to identify the spare parts that comprise the air conditioner system. To identify the body and the chassis, their manuals should be consulted. 11

12 4.4. CC 350 Modelnumber

13 4.4. CC 350 Modelnumber Serialnumber Fan QTY Blower QTY CC350-RT-SPG1-01 WG WG CC350-RT-SPXXG1-01 XXX 0 WG CC350-RT-XXHE-01 XXX 0 XXX 0 CC350-RT-SPG2-HF-01 WG WG

14 4.5. CC 350 Equipment Components No. Name Reference-No Condenser - left Coil -right 2 Condenser Fan 12 24V CC CC WG Filter Dryer WG Service Valve WG Evaporator Coil right CC Relay Plate WG Evaporator Coil left 8 Evaporator Blower 9 Temperature Sensor CC WG WG Expansion Valve WG Receiver WG (opt.) 13 (opt.) Heating - left Coil - right Fresh Air CC350H CC350H CC

15 4.6. Refrigerant Circuit No. Name 1 Refrigeration Compressor 2 Condenser 3 Receiver 4 Filter Dryer 5 Expansion Valve 6 Evaporator 7 Cold Air 8 Warm Air 9 Temperature Sensor 10 Blower 11 Sight Glass 12 Filling Fixture (for servicing only) 13 Pressure Switch 14 Hot Air 15 Outside Air 16 Fan 15

16 4.7. CC 350 Installation Drawing

17 5. Controller & Operating March

18 5.1 Controller WG No. Description No. Description 1 Blower and Air Conditioning OFF (0) 5 Blower and Air Conditioning Switch 2 Blower and Air Conditioning Low Mode (1) 6 Cooling Compressor LED 3 Blower and Air Conditioning High Mode (2) 7 Temperature Adjust Switch 4 Blower and Air Conditioning Auto- Regulation Mode (AUTO)

19 5.2. Controller WG Operating The air conditioner control panel WG has two control switches, one for the blower speed and one for the temperature adjustment. It also is featured with has an LED indicator to signal the activation of the air conditioning clutch. Temperature Adjust Switch The Temperature Adjust Switch (7) is used to set the ideal or desired temperature value of the user. This can be varied between approximately 18 C and 26 C. The system is then automatically regulated when the set value is attained. Cooling Compressor The Cooling Compressor LED (6) lights blue whilst the air conditioning compressor clutch is activated, the condenser fans are running and the cooling is taking place. The LED goes off when the cabin temperature falls to the level the user has set. Blower and Air Conditioning Switch The blowers have three modes of activation by the Blower and Air Conditioning Switch (5) Low (2), High (3) and Auto-regulation (4). The blowers do not run and no cooling takes place at the OFF position (1). The Low and High switch positions keep the blowers continuously running at low or high fixed speed respectively, independent of the set or actual temperature values. In Auto-regulation mode, the speed of the blowers is low when the cabin temperature is below the set value. The speed becomes high when cooling is taking place and the actual cabin temperature exceeds to the users set. High speed blowing starts only after the temperature difference exceeds to + 2 C between the set value and the cabin temperature. It stops when the cabin temperature is equal to the set value.

20 5.3. Controller W 163 Numeric Display Automatic Control Key Temperature Increase Key Ventilation Control Key Temperature Decrease Key Air-Refreshment Control Key 20

21 5.4. Numeric Display Set-point The Air conditioning electronic control is a micro processed equipment developed to control the temperature of the most kind of bus. The control panel and the power board form together the electronic control. The control panel is connected by a half-duplex serial communication channel. The system can control the refrigeration and the heating at same time. Numeric Display The two digits Numeric Display is used for informing the operator how is the system working. When there is no function active, the display shows.. Normally the display shows the Set-point when in Automatic Control Mode or the blower speed when in Ventilation Mode. Beside this, the Numeric Display also shows the different operation modes and fails. Set-point The Set-point is the desired temperature inside the vehicle. To change the Set-point, it is necessary, that Auto Mode is selected. After pressing the Automatic Control Key, the display will show the Set-point and may be adjusted by pressing the Temperature Increase or Temperature Decrease Key. and set the minimum and maximum limits for the Set-point adjustment. If both parameters are programmed with the same parameter, adjusting the temperature is blocked and the display blinks, to indicate that this adjustment is not available.

22 5.5. Reading the temperature Ventilation Mode Reading the temperature The controller monitors temperature sensors, arranged in the vehicle as described below: a) Internal temperature sensor - located in the air return duct. b) External temperature sensor* - located outside the air-conditioner. c) Duct temperature sensor * - located in the air ducts. * only in systems that have heating mode. Ventilation Mode The Ventilation Mode is selected by pressing the Ventilation Control Key There are three operation blower speeds. To change the blower speed, it is necessary, that Ventilation Mode is selected. After pressing the Ventilation Control Key the speed will be shown and may be adjusted by pressing Temperature Increase or Temperature Decrease Key. The three operation blower speeds will be indicated on the Numeric Display and by the Ventilation speed indicators low, middle and high. Display Off Low Speed Middle Speed High Speed Indicator When you select the Ventilation Mode, the damper (air renovation) is automatically opened. For closing the damper, the operator has to press the Air-Refreshment Control Key and the Temperature Decrease Key.

23 5.6. Automatic Control Mode Automatic Control Mode The Automatic Control Mode provides a full automatic control inside the bus. You just need to press the Automatic Control Key and set the desired temperature. The system is designed to work by itself in order to select the best operation mode to reach the set point. You can also use the Automatic Control Mode with your desired blower speed. After pressing the Automatic Control Key, the Numeric Display will show the Set-point and the system will start the appropriate function cooling or heating, according to the internal temperature, external temperature, Set-point and parameters. The Automatic Control Mode is turned off by pressing the Automatic Control Key again. The system will automatic keep the temperature nearby the Set-point by alternately switching between heating mode and cooling mode. The system also controls the evaporator with three different blower speeds. They always start at a low speed and, if necessary, the speed is increased up to the desired one to keep the temperature at the Set-point. Blower speed will be decreased when the temperature gets near the Set-point. Manual control of blower speed: In Automatic Control Mode, the blower speed usually is set automatic, but it is also possible to control the blower speed manual by starting the Automatic Control Mode. then press the Ventilation Control Key. The blower speed will be shown for a few seconds on the Numeric Display. The Operator has then to press the Temperature Increase Key or the Temperature Decrease Key to increase/decrease the blower speed. After this, the blower speed is set to manual control and the ventilation speed indicators low, middle or high will turn on. To turn back to the Automatic Control Mode, just press the Automatic Control Key.

24 5.7. Refrigeration Compressor Fans Refrigeration The refrigeration cycle is analyzed through the graph on the right side where it is possible to see under which operation conditions the system activates the refrigeration (compressor). The parameter must be set to count the number of ignition starts. When this number is reached, the refrigeration system is forced to be on for 2 minutes. After this time it elapses, the system goes back to normal operation and the counter of ignition starts is reset and starts a new counting. The system components operate according to what is described below: Compressor: The compressor is activated in accordance with the temperature, the pressure switches and the programmed values at the Set-point and the parameters. The compressor will just turn on 10 seconds after the condenser motors are turned on. The controller presents a time hysteresis fixed at 60 seconds for turning the compressor back on, that is, the compressor will be kept off for a minimum time of 60 seconds before being turned on again Fans condenser motors: The fans will turn on every time there is the need to turn on the compressor. They will always turn on 10 seconds before turning the compressor clutch on.

25 5.8. Pressure switch ICE sensor System pressure switch: The system monitors its high and low pressure by means of serial pressure switches connected with the clutch. They are constantly monitored by the control board. If a pressure failure happens, the clutch will be turned off immediately. In this case, the system will acknowledge the failure after 2 seconds and will start indicating at the display, alternating it with the temperature reading. As soon as the pressure problem is over, the system will wait for a period of 3 minutes so that the compressor may be activated again, in case the Automatic Control Mode is activated and the other conditions have been met. This alarm is constantly monitored, independently whether the system is on or not. As you may notice, the alarm may be indicated even if the Automatic Control Mode. In case this alarm fails 6 or more times within an interval smaller than 30 minutes, the alarm will be activated, indicating the system presents a serious system failure and blocking air conditioning operation. The system can operate only in ventilation or heating mode. In order to turn A/C on again, it will be necessary to turn the vehicle off and then on again ICE sensor Freezing of the Evaporator Serpentine The system presents a device for monitoring the status of the thermostat, which evidences the freezing of the evaporator serpentine. When such a device is activated (open contact), the compressor clutch is turned off, and the blowers (evaporator motors) are kept in operation in order to allow the defrosting of the serpentine. While the thermostat is activated, the panel will indicate the failure code (ICE), alternating it with the temperature display. After being defrosted, the thermostat will once again indicate normal operation. The system waits for 3 minutes and, in case the Automatic Control Mode is still on, the compressor will be turned on again.

26 5.9. Heating Auxiliary Heaters Heating The heating cycle is analyzed through the graph on the right side where it is possible to see under which operation conditions the system activates the heating. Heating will be available when the set is accompanied with GL-W003 module for the controller GL-W521 or with the GL-W004 module for the controller GL-W111. The board will automatically recognize it and when the board is connected to the system, it will effect the due Enabling. Heating acts over a slave valve, with PID algorithm. This valve controls the flow of hot water passing through the A/C radiator. It presents a water pump, which is turned on every time the valve is with an opening percentage larger than the one programmed at the parameter. The system also has a function that open and close the motor valve each time the system is turn on. This is useful to remove all the unexpected parts (dirty) that can stay on the line due to a long time closed (during hot season). So, the valve will be available and operating when cold season arrives. In case a value higher than zero is programmed at the parameter, the system may operate with Reheating Mode. Auxiliary heaters The heating mode for auxiliary heaters are activated in the same way as the heating mode in Automatic Control Mode. Providing the internal temperature of the vehicle is below the Set-point, the equipment will start operating. Auxiliary heaters are side wall heater and under seat heater based on convection only or with own blower. They are usually installed by the body manufacturers.

27 5.10. Air Refreshment Mode Air Refreshment Mode The system controls one motorized air flap. There are two system operation modes: - Smart Air - Manual Mode The Air Refreshment damper operates at both modes. The Smart Air mode automatically controls according to the temperature conditions (internal, external and for renovating the air inside the vehicle). The Manual Mode allows the driver to control the opening of external air manually. When the Automatic Control Mode is activated, it is selected Smart Air, indicated at the panel by the least significant digital point from the display. This operation enables the damper to operate in a way that it always seeks for the best comfort and thermal balance conditions as well saving fuel. To change the damper state, press the Air Refreshment Key and the panel will shows the damper state: - = open and = closed When the damper state is shown, press the Temperature Increase Key to open or the Temperature Degrease Key to close the damper door. The display point will turn off and the Manual Mode is taken over. After the elapsed time of the parameter (in minutes), the system came back to operate in the Smart Air mode. In the Smart Air mode, the fresh air flap opens and closes automatically and the cycle is according to the parameters (time opened in seconds) and (time closed in minutes). This will just happen when the internal temperature is between 3ºC over Set-point and 3ºC below Set-point. When the internal temperature is below 15ºC in cool mode, the system tries to cool down only with fresh air. The clutch waits 1 minute to engage. After elapsed this time the system checks if temperature reduces at least one degree. These are repeated until the temperature did not reduce 1ºC each minute, then the clutch is engaged. In the Manual Mode the damper state is indicated by the AIR RENOVATION led (only when opened).

28 5.11. Operation without panel Operating without panel When ignition is turned on, the Control panel and the Control board intercommunicate with one another. In case there is a communication failure between them, the panel will indicate after 15 seconds and the Control board will turn automatically on the Automatic Control Mode, with a previously stored setpoint. This is a failure condition, although it enables the equipment to work even without communication between the modules. If the equipment is operating and there is a communication failure, it will keep on operating on the selected function until ignition is turned off.

29 6. Maintenance, Troubleshooting March

30 6.1. Preventive Maintenance PREVENTIVE MAINTENANCE To ensure the perfect performance of the air conditioner it is necessary to perform preventive maintenance routines. This will avoid loss of cooling capacity, extend the life of equipment s parts and reduce unnecessary stops of the vehicle. SECURITY WARNING 1) Personal protection The air conditioning system offers chemical, mechanical and electrical hazards. So it is essential to use PPE (Personal Protective Equipment) to protect your from: refrigerant, oil, battery acid, debris and engine noise. 2) High pressure The refrigerant in liquid form under high pressure is a potential risk. If released to the environment the refrigerant can cause serious damage to the eyes and skin. 3) Hoses Check if the manometer hoses are able to be used and move away from the belts, pulleys and hot surfaces. 4) Hot surfaces The compressor discharge, exhaust and other engine components can be very hot. 5) Components in rotation The fans, pulleys and belts may not be visible under certain conditions. Special care must be taken in approaching with hands. 6) Welding The welding should be made with caution, because it can cause burns and emit some toxic gases. Make sure you are in a ventilated place. 7) Toxic gas The refrigerant gas in the presence of flame produces a toxic gas that can cause severe respiratory irritation. Take special care indoors, where the refrigerant can cause shortness of breath. 8) Other precautions Care should be taken using ladders and platforms, as there is a danger of slipping and falling. Use full body harness whenever it s necessary to work in places over 1.5 meters. Never apply heat in containers or pressurized lines. Never turn the equipment on with the discharge shut-off valve blocking the refrigerant flow. The refrigeration oil can cause irritation to the skin and eyes, so avoid prolonged contact. Make sure that all screws are the right length and with the correct grip. All components that are not in perfect condition should be replaced for security reasons. 30

31 6.1. Preventive Maintenance REFRIGERANT GAS R-134a Spheros products only use refrigerant R134a. Using gas refrigerant with different characteristics, low quality or doubtful provenance could cause low capacity and damage other equipment components. ATTENTION: Under no circumstance can refrigerant be discharged into the atmosphere. OIL The compressor oil must be replaced every time it shows a change in color. a) Yellow = normal oil; b) Black = carbonized oil; c) Brown = copper attack, due to humidity in the system; d) Metallic gray = suspended metallic particles. We recommend the preventive oil replaced every 3 years or hours of work, whichever occurs first. DRIER FILTER The filter drier must be replaced every time a maintenance is done and the system lost gas load or was exposed to contamination. We recommend a preventive filter replacement once a year. CLUTCH When perform cleaning in the clutch take care to avoid dirt depositing between the faces of the friction disc. COMPRESSOR SEALING The oil felt seal must be cleaned or replaced whenever it is saturated. To avoid leaking of the compressor mechanical seal by lack of lubrication the air-conditioner system must be in the cooling mode once every 15 days at least 15 minutes. AIR DUCTS The air duct cleaning must be carried out every thee months. Such time may be reduced in accordance with the use of the air-conditioner system, the number of people to be transported as well as the environmental conditions. The owners of the vehicles are entirely responsible for the cleaning process; they will be held accountable for any cost resulting from the bad quality of air offered to their passengers. Note: Ducts are part of the bus body.!!! SAY NO TO NON-ORIGINAL PARTS!!! The use of non-original parts will decrease the efficiency of air conditioner, overloads of the electrical system may cause premature compressor failures and even cause fires. IMPORTANT: The preventive maintenance actions should be undertaken by the vehicle owner. The failure to carry out these events may be classified as negligence, thereby cancelling the warranty. ATTENTION: Should any problem in the cooling system occurs, the repair must be carried out by an authorized service station or an expert. 31

32 6.2. Preventive Maintenance Frequency Schedule WEEKLY MONTHLY QUARTERLY EVERY SIX MONTHS ANNUAL 1 - Clean or change the air return filter. 2 - Inspect the general conditions, the tensioning and the alignment of the compressor and alternator belts. 1 - Perform the weekly preventive maintenance routines. 2 - Clear the condenser coil. (Use only mild soap and water, not abrasive to cooper and aluminum). 3 - Check the evaporator hoods closure to prevent the entry of false air into the equipment. 4 - Check the refrigerant gas load: After 15 minutes of operation the refrigerant must flow through sight glass without bubbles. 5 - Check the compressor oil level: After 15 minutes of operation it must be between 3/4 and 1/4 of the sight glass. 6 - Test the equipment functions: cooling mode/ ventilation mode (high and low speed)/ heating/ air refreshment. 1 - Perform the monthly preventive maintenance routines. 2 - Measure the suction and discharge pressure and check the temperature and condition of the suction line. 3 - Tighten the alternator power cables, main fuse, relay plate and starter. 4 - Measure the current consumption of the condenser fans and the evaporator blower (check the air flow). 5 - Measure the magnetic resistance of the clutch. 6 - Measure the voltage and current of the alternator. 1 - Perform the quarterly preventive maintenance routines. 2 - Clean the evaporator coil (use only mild soap and water, not abrasive to cooper and aluminum). 3 - Clean the evaporator drains. 4 - Check the retention of oil felt of compressor sealing. 5 - Visually check the air conditioner components to see whether they show signs of leaking refrigerant and oil. 6 - Observe if there are parts loose, damaged, broken or showing signs of wear, rust, deterioration and friction with the body. 1 - Perform the six months preventive maintenance routines. 2 - Test compressor efficiency at 1500 rpm. 3 - Check the compressor oil pump pressure at 1000 rpm. 4 - Check the open and closure pressure of the high and low pressure switches. 5 - Tighten all screws from the compressor support and the unit, observing the applied torques. 6 - Remove dirt deposited on the components condenser, controller, relay plate, compressor, clutch, alternator. All preventive maintenance described in this manual is considered for operating under normal conditions. Should the conditions be other than expected and environmental contamination a possibility, the frequency of actions must be more intense. 32

33 6.3. Troubleshooting General Like all parts of the vehicle, the air conditioning system is subject to constant stresses. It must therefore be serviced regularly by specialists with experience of refrigeration systems in order to ensure troublefree operation and to prevent damage to the system parts. Correct treatment of the system and proof that all the specified service work has been carried out (completed maintenance and service schedule) are essential for acceptance of warranty claims concerning damage to parts subject to maintenance. Regardless of the intervals specified in the maintenance and service schedule, all equipment connections and the refrigerant lines must be checked during the first four weeks after commissioning the air-conditioning system and/or vehicle to ensure that they are secure. Even if the air-conditioning system is not used, individual components may suffer wear due to normal ageing or stress resulting from operation of the bus. The inspections specified in the maintenance and service schedule must therefore be carried out regardless of the time during which the system is actually operated. Refrigerant loss may occur even if there are no leaks in the lines. Due to the structure of the material used for the refrigerant hoses, their diffusion rate can vary depending on ambient temperature. However, a leak must be assumed to exist somewhere in the system if relatively large quantities of refrigerant are lost at short intervals. To prevent not only the shaft seals of the refrigerant compressor drying out, but also moving parts in the refrigerant circuit from seizing up due to resinification of the oil, the air-conditioning system must be switched on for approx. 15 minutes at least once per month when it is not in regular use. The outside temperature must be over at least 5 C or the bus must be in a heated garage during this trial run. The belt pulley of the electromagnetic clutch rotates constantly when the engine is running. Bearing wear and the possibility of damage to the clutch are therefore more or less independent of the time during which the air-conditioning system is operated. It is therefore essential to check the clutch for dry running of the bearings etc. as instructed. IMPORTANT: The refrigerant receiver is subject to the requirements of the German regulation on pressure vessels and must be examined for cracks, corrosion and other signs of damage every six months. The receiver must be replaced if cracks, mechanical damage or corrosion are observed. The intervals specified in the maintenance and service schedule refer to the vehicle's hours of operation, except in the case of the compressor, where they refer to the hours of operation of the air-conditioning system. The specified intervals are empirical values and can vary considerably depending on the type of system and type of bus. The maintenance intervals always refer to the first event occurring. 33

34 6.4. Troubleshooting Faults Electrical faults The individual circuits must be systematically checked in accordance with the circuit diagram. Plug connections and such electrical components as switches, relays, etc. should preferably be checked for continuity at the same time. The following fault causes must always be checked to exclude the possibility of faults due to any of these causes: Corrosion of plug contacts Loose contact in plug connectors Corrosion on wiring Corrosion on battery poles Abraded wiring Correct operation of fuse Faults in the air-conditioning system The following faults may occur in the air-conditioning system and disable it: Activation of the defrost system Activation of the high-pressure / low-pressure switch Defective refrigerant compressor Defective evaporator or condenser fan Loss of refrigerant due to leaks Soiled air filters or heat exchanger fins Blockage in the refrigeration system (e.g. filter drier) Defective expansion valve Faults in the refrigerant circulation If faults develop in the refrigerant circulation, the air-conditioning system must be checked and repaired by an authorized specialist workshop. IMPORTANT: The refrigerant must not be discharged into the atmosphere (Section 8 of the regulation dated banning CFCs and halon compounds). NOTE: To ensure trouble free operation of the air conditioner, the refrigeration oil and the filter drier must be replaced 6 months after the initial operation of the vehicle. The filter drier should be replaced every year at the beginning of the season. These activities are to be performed by an authorized qualified workshop, which should also perform a functional check of the air conditioner as well as a leak test. Warranty claims can only be accepted if the claimant can prove that the maintenance and safety instructions have been strictly observed. 34

35 6.5. Troubleshooting Failure Diagnosis Table For troubleshooting the following failure diagnosis table lists possible malfunctions and symptoms and the remedial action to be taken to restore the system's serviceability. Symptoms Probable Cause Solution Compressor does not work Low suction pressure High discharge pressure Fuse or relay defective Magnetic clutch burned Compressor blocked Low pressure switch open Lack of refrigerant Air return temperature is too low Dirty or defective expansion valve Evaporator motor is stopped Restriction in the system Loaded air filter Dirty evaporator coil Excess refrigerant in the system Refrigerant flow obstructed Condenser motor is stopped Dirty condenser coil Replace fuse or relay Repair or replace clutch Repair or replace compressor Lack of gas on system or defective low pressure switch Check for leakage, fill to correct amount Place the temperature sensor at the most appropriate position Clean or replace the valve Replace motor Eliminate Clean or replace filter Clean coil Drain and capture refrigerant, fill to correct amount Check for restriction (compressor valve partially closed, expansion valve blocked, filter dryer blocked, etc.) Refer to symptom Condenser motor is stopped Clean and wash 35

36 6.5. Troubleshooting Failure Diagnosis Table Symptoms Probable Cause Solution AC does not cool down and the compressor remains on Cools down too much, compressor does not turn off Condenser motor is stopped Lack of refrigerant Air or other gas in the system Dirty or defective expansion valve Dirty evaporator coil Air filter dirty Incorrect temperature selection Temperature sensor badly placed Electric wiring connections with no contact Condenser motor is stopped Burned fuse or defective relay Check for leakage, fill to correct amount Draw a vacuum (min. 3h below 10mbar) replace filter dryer, fill to correct amount Replace the valve Clean the coil Clean or replace filter Adjust the temperature on the control panel Place the sensor appropriately Repair wiring harness Replace condenser motor Replace fuse and / or relay HP switch opens Excessive refrigerant Drain and collect excess refrigerant Condenser coil is dirty Condenser motor / motors stopped Clean the coil Replace motors LP switch opens Lack of refrigerant Check for leakage, fill to correct amount Dirty or defective expansion valve Dirty evaporator coil Excessively contaminated air filter Evaporator ventilator is stopped Replace the valve Clean the coil Replace the filter Replace the evaporator fan 36

37 7. Technical Data Sheet Overview March

38 7. Technical Data Sheet Overview AIR CONDITIONER Model Capacity CC kW CC kW CC kW REFRIGERANT GAS Type Quantity R-134a 7,5 kg* R-134a 7,5 kg* R-134a 8,5 kg* EVAPORATOR Blower model Quantity of blowers Air flow (free blowing) Nominal current centrifugal m 3 /h 46 A centrifugal m 3 /h 69 A centrifugal m 3 /h 69 A CONDENSER Fan model Quantity of fans Air flow (free blowing) Nominal current axial m 3 /h 27 A axial m 3 /h 27 A axial m 3 /h 36 A COMPRESSOR Model (type alternative) Displacement Max. rotation Lubricating oil Quantity of oil Bitzer 4TFCY 470 cm rpm ml Bitzer 4PFCY 558 cm rpm ml Bitzer 4NFCY 647 cm rpm ml CLUTCH Type Voltage electromagnetic 24 V electromagnetic 24 V electromagnetic 24 V 38

39 7. Technical Data Sheet Overview AIR CONDITIONER Model Capacity A350 Tropical 40 kw CC kW / 43kW REFRIGERANT GAS Type Quantity R-134a 8 kg* R-134a 8,5 kg* EVAPORATOR Blower model Quantity of blowers Air flow (free blowing) Nominal current centrifugal m 3 /h 69 A centrifugal m 3 /h 69 A CONDENSER Fan model Quantity of fans Air flow (free blowing) Nominal current axial m 3 /h 45 A axial m 3 /h 45 A COMPRESSOR Model (type alternative) Displacement Max. rotation Lubricating oil Quantity of oil Bock FK40 / 655K 650 cm rpm Reniso Triton SE ml Bock FK cm 3 / 647 cm rpm Bitzer BSE ml CLUTCH Type Voltage electromagnetic 24 V electromagnetic 24 V 39

40 8. Notes March

41 8. Notes 41