Luft-Heizgeräte Air Heaters 03/2003 Workshop Manual Air Top 2000 ST Type Air Top 2000 ST B (petrol) Type Air Top 2000 ST D (diesel)
Improper installation or repair of Webasto heating and cooling systems can cause fire or the leakage of deadly carbon monoxide leading to serious injury or death. To install and repair Webasto heating and cooling systems you need to have completed a Webasto training course and have the appropriate technical documentation, special tools and special equipment. Only genuine Webasto parts may be used. See also Webasto air and water heaters accessories catalogue.
Air Top 2000 ST Table of Contents Table of Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 1.1 1.2 1.3 1.4 2 General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 3 Contents and purpose. . . . . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents 6 Function Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601 6.1 6.2 6.3 6.4 7 601 601 602 602 603 603 604 605 607 609 610 611 612 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 701 Legend for circuit diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Top 2000 ST 9 Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 901 9.1 9.2 10 Table of Contents General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 901 9.1.1 Work on stripped down components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
List of Illustrations Air Top 2000 ST List of Illustrations Fig. 201 Fig. 202 Fig. 203 Fig. 204 Fig. 205 Fig. 206 Fig. 207 Fig. 208 Fig. 209 Fig. 210 Fig. 401 Fig. 402 Fig. 501 Fig. 502 Fig. 503 Fig. 601 Fig. 701 Fig. 702 Fig. 703 Fig. 704 Fig. 705 Fig. 706 Fig. 801 Fig. 802 Fig. 803 Fig. 804 Fig. 805 Fig. 806 Fig. 807 Fig. 808 Fig. 809 Fig. 810 Fig. 811 Fig. 812 Fig. 813 Fig. 814 Fig. 815 Fig. 901 Fig. 902 Fig. 903 Fig. 904 Fig. 905 IV Air Top 2000 ST air heater . . . . . . . . . . . . . . . . . . . .
Air Top 2000 ST 1 Introduction 1.1 Contents and purpose This workshop manual is designed to assist trained personnel, with repairing both the petrol and the diesel versions of the Air Top 2000 ST air heaters. 1.1.1 Use of the air heaters The Webasto Air Top 2000 ST air heaters are designed – to heat cabins, boats, trucks, minibuses, vans, ambulances and motorhomes – to defrost vehicle windows They are not designed for heating cargo areas used to carry hazardous substances.
Introduction 2.2. / 5.3.2. (Part I) Positioning of heater 2.6. / 5.3.6. (Part I) Heating air inlet 2.2.1. / 5.3.2.1. (Part I) Body sections and any other components in the vicinity of the heater must be protected from excessive heat and the possibility of fuel or oil contamination. 2.6.1. / 5.3.6.1.
Air Top 2000 ST Introduction 1.4.2 General safety information The mouth of the exhaust pipe should be installed upwards, to the side or, if the exhaust pipe passes under the floor of the vehicle, to the side or rear limit of the driver’s cab or the vehicle. The function of important parts of the vehicle must not be adversely affected. It must not be possible for condensate or water to collect in the exhaust pipe. Drain holes may be used.
Introduction NOTE If any damage or leaks are found on the fuel line, the heater must not be used until the damage has been rectified by an authorised Webasto workshop. Put the heater out of action by removing the fuse. Overheating Keep the hot air inlet and hot air outlet free of dirt and foreign bodies. Dirty, blocked air lines can cause the heater to shut down due to overheating.
Air Top 2000 ST 2 General description The Air Top 2000 ST air heaters are based on the evaporator principle and essentially consist of the following – – – – General description If a fault occurs, an error code will be output in the display of the combination or standard timer. If the heater has a control element, the ON control light will flash. In addition the heater can be checked using a personal computer (see PC heater diagnostic operating manual).
General description 2.2 Air Top 2000 ST Heat exchanger 2.4 The heat generated by the combustion process is transferred to the air transported by the combustion and hot air blowers in the heat exchanger. Control unit The control unit is the central component for ensuring the function is maintained and for monitoring the heater’s operation. A temperature sensor in the control unit is designed to control the room temperature. An external temperature may also be connected to all the heaters.
Air Top 2000 ST 2.6 Glow plug The mixture of fuel and air is ignited by the glow plug when the heater is started. The glow plug takes the form of an electrical resistor and is positioned in the burner insert on the side away from the flame. General description 2.8 Metering pump The metering pump is a combined transport, metering and shut-off system for supplying fuel from the vehicle’s tank to the heater. Fig. 210 Metering pump DP2 / DP 30.2 Fig. 208 Glow plug 2.
General description Page for notes 204 Air Top 2000 ST
Air Top 2000 ST 3 Description of operation 3.1 Control element The control element is designed to switch the heater on and off, adjust the required room temperature (intake temperature between approx. 5 °C and 35 °C) and to reset the heater after a fault. The green LED serves as the On indicator (LED permanently lit up) and as a fault signal (LED flashes).
Description of operation If, at minimum heat output, the intake temperature set on the control element is exceeded, the metering pump is shut down and the combustion process ended. To burn off the flame properly the blower speed falls after 20 seconds to low-fire rate speed and then returns to the initial speed after 15 seconds, after which it falls to the control pause speed in 3 minutes, where it remains for the entire control pause. The control pause speed on boat heaters is 0.
Air Top 2000 ST Description of operation If the FAZ reaches a value of 6, the heater will go into fault lock-out mode and the permanent flame failure counter FAZP will be incremented by 1. In control mode the permanent flame failure counter FAZP will be decremented by 1. When the heater is burning properly again, the FAZP will return to 0 after a few control cycles.
Description of operation Page for notes 304 Air Top 2000 ST
Air Top 2000 ST 4 Technical data Technical data Except where limit values are specified, the technical data listed in the table refer to the usual heater tolerances of ± 10% at an ambient temperature of + 20 °C and at the rated voltage and in rated conditions. Electrical components: The control unit, combustion air blower (drive), metering pump, timer*, glow plug and control element are designed for 12 V or 24 V.
Technical data Air Top 2000 ST Setpoint values: 12 V Glow plug At 25 ºC Test current: < 5 mA Drive unit Outside Overheating temperature sensor at 25 ºC Undervoltage switch-off (triggering time > 20 s ) Overvoltage switch-off (triggering time > 6 s ) red marking 0.263 - 0.323 ohms 24 V Green marking 1.125 - 1.375 ohms < 6 ohms 2- 2.5 ohms. ≤ 10.5 V ≤ 20.5 V ≥ 15 V ≥ 31 V Fig.
Air Top 2000 ST Troubleshooting 5 Troubleshooting 5.1 General This section describes how to identify and remedy faults on the Air Top 2000 ST air heater. If a fault occurs, an error code will be output in the display of the combination timer. If the heater has a control element, the ON control light will flash. In addition the heater can be checked using a personal computer (see PC heater diagnostic operating manual).
Troubleshooting 5.3 Air Top 2000 ST Error symptoms during function The following table (Fig. 502) lists the possible error symptoms in the order in which they may occur during operation. In the event of a fault, the error is to be located using this table and rectified. It is important that the error symptom is correctly identified.
Air Top 2000 ST 5.4 Troubleshooting Error code output If the heater is fitted with a combination timer, an error code output will appear on the display of the timer after a fault occurs. NOTE The error code is output if the heater is fitted with a control element after an error has occurred by the switch-on indicator/error code indicator flashing.
Troubleshooting Air Top 2000 ST Error code Error (group) Additional information during PC diagnostic Troubleshooting F 05 Flame monitor interrupt or short circuit (only petrol heater) 1A Flame monitor circuit The switched cable of the element has a short circuit to earth Replace flame monitor 9A Flame monitor circuit interrupt or short circuit to +Ub Replace flame monitor 14 Temperature sensor circuit short circuit to earth Check cables/ replace temperature sensor 94 Temperature sensor circuit
Air Top 2000 ST Troubleshooting Error code Error (group) Additional information during PC diagnostic Troubleshooting F 12 Heater unit lock-out 07 The permanent heater fault lock-out has been activated Remove the fuse and reinsert it NOTE The following error has occurred several times: Fault counter more than 3 times Incorrect start counter more than 9 times Overheating counter more than 3 times F 14 Overheating sensor incorrect position 97 Incorrect position of the overheating sensor (OHS gradie
Troubleshooting Page for notes 506 Air Top 2000 ST
Air Top 2000 ST 6 Function Tests 6.1 General This section describes the tests conducted on the heater when it is installed and not installed to verify that it is in working order. WARNING The heater must not be operated in enclosed areas such as garages and workshops without an emissions extraction system. IMPORTANT Complete testing of heater and control unit test for “OEM” heaters only possible in conjunction with vehicle. 6.
Function Tests Air Top 2000 ST 6.3 Settings 6.3.1 Setting CO2 content The CO2 content in the emissions is set using the adjustment knob on the control element. At a constant blower speed the volume of fuel is controlled by changing the metering pump cycle. IMPORTANT The CO2 measuring instruments must be calibrated. The heater must be switched off. 1. Connect the CO2 line to minus. 2. Turn the adjustment knob on the control element to the centre setting.
Air Top 2000 ST Function Tests 6.3.2 CO2 setting of reference heater 6.4 Testing individual components The reference heater is set to 10.3 vol.% CO2 at a geodetic altitude of 0 metres at the factory. For later resetting, a CO2 value must be set in accordance with the following table as per the geodetic altitude. IMPORTANT For function tests always disconnect the connection between the control unit and the component to be tested.
Function Tests Air Top 2000 ST 6.4.1 Burner insert component See Fig.
Air Top 2000 ST Function Tests 6.4.2 Glow plug resistance test (only petrol heater) See Fig. 904, Item 1 If you conduct this test with a digital multimeter, the flame monitor must have the values shown as following: Cold testing: Resistance at 25 °C: Test current: 2.6 - 3.4 ohms. < 5 mA Hot testing: Resistance at 800 -1000 °C: 12 - 15 ohms. Test current: < 5 mA (ceramic rod at red heat over length of approx.
Function Tests Air Top 2000 ST Procedure Flame monitor Contacts detached? yes 2 Visual inspection 2 Visual inspection A Visual inspection Testing and measuring equipment no yes Cables damaged? no Ceramic broken? yes no Resistance outside 2.5 - 3.
Air Top 2000 ST Function Tests 6.4.3 Glow plug component See Fig. 904, Item 6 NOTE The resistance test must be carried out with an ohmmeter suitable for small resistance values. A resistance test with a simple digital multimeter is too inaccurate to find the precise values. A new glow plug can be measured to act as a reference. The glow plug should have the following values in the test: Glow plug: 12 V (red) Resistance at 25 °C: 0.263 - 0.323 ohms Test current: < 5 mA 24 V (green) 1.125 - 1.
Function Tests Air Top 2000 ST Procedure Glow plug Contacts detached? yes 2 Visual inspection 2 Visual inspection A Visual inspection Testing and measuring equipment no yes Cables damaged? no Ceramic broken? yes no Resistance outside 1.1 - 1.
Air Top 2000 ST Function Tests 6.4.4 Combustion air fan component (drive) See Fig. 903, Item 5 Procedure Testing and measuring equipment Visual Combustion air fan (drive) Externally damaged? yes 2 Visual inspection no Installation of component in unit => short circuit to metal parts (heat exchanger etc.
Function Tests Air Top 2000 ST 6.4.5 Overheating sensor component If you conduct this resistance test with a digital multimeter, the overheating sensor must have the values shown in the following diagram (Fig. 601). Resistance in ohms See Fig. 903, Item 8 Temperature in °C Fig.
Air Top 2000 ST Function Tests 6.4.6 Control unit component See Fig. 701 and Fig.
Function Tests Air Top 2000 ST 6.4.
Air Top 2000 ST Function Tests Description A Procedure Testing and measuring equipment Function test – Heater test bench – PC (personal computer) – Webasto Diagnosis Adapter Check function on heater test bench Reading out control unit data: Burning hours, number of starts, errors Send printouts of diagnosis with component to Webasto (for contact, see beginning of paragraph 6.
Function Tests Air Top 2000 ST B Description Procedure Testing and measuring equipment Replace component and continue Function test – Heater test bench – CO2 measuring unit – PC (personal computer) – Webasto Diagnosis Adapter – Reference heater Control unit test in reference heater Fault-free operation in reference heater? no 3 yes Reinstalling control unit in heater to be tested CO2 value within tolerance? no Set CO2 value in permissible range with adjusting screw C 614 yes 2 CO2 measure
Air Top 2000 ST Function Tests C CO2 value adjustable? yes Description Procedure Conduct function test with reference heater.
Function Tests Page for notes 616 Air Top 2000 ST
Air Top 2000 ST Circuit diagrams 7 Circuit diagrams The circuit diagrams (Fig. 702 to Fig. 705) show the possible circuits for 12 or 24 Volt with 7.1 General • • • • The Air Top 2000 ST heater units can be operated with the heater control (setpoint generator/switch) or a combination timer. Control element and vehicle blower Combination timer and vehicle blower ADR operation with control element Combination timer and electrical battery isolation switch Fig.
Circuit diagrams Air Top 2000 ST Fig. 702 System circuit diagram Air Top 2000 ST, 12V/24V with control element and vehicle blower Fig.
Air Top 2000 ST Circuit diagrams Fig. 704 System circuit diagram Air Top 2000 ST, 12V/24V ADR operation with control element Fig.
Circuit diagrams Air Top 2000 ST Combination timer 1531 black: Terminal 15 red: Terminal 30 grey: Terminal 58 brown: Terminal 31 Adapter wiring harness Fig.
Air Top 2000 ST 7.2 Circuit diagrams Legend for circuit diagrams Cable cross-sections Item A1 A2 B1 B2 B3 B4 E F1 < 7.5 m 7.5 - 15 m 0.75 mm2 1.0 mm2 1.0 mm2 1.5 mm2 1.5 mm2 2.5 mm2 2.5 mm2 4.0 mm2 4.0 mm2 6.0 mm2 F2 Description Heater Control unit Flame monitor Temperature sensor Overheating sensor Temperature sensor Glow plug Fuse 15 A 12V/ 24 V (max.
Circuit diagrams Page for notes 706 Air Top 2000 ST
Air Top 2000 ST Servicing work 8 Servicing work The following servicing work is to be carried out to maintain the functional reliability of the heater: 8.1 General • This section describes the servicing work that can be carried out on the heater when it is installed. • • 8.2 Work on the heater Disconnect the main power cable from the vehicle’s battery before carrying out any work on the heater.
Servicing work Air Top 2000 ST IMPORTANT In vehicles used to transport people, the air outlet opening is to be installed in such a way that it is at least 20 cm away from all body parts. The heaters check the internal temperature rise automatically each time they are switched on. If this is above the specified limits, the start is cancelled and error messages F10 is displayed. To ensure that the heater functions stably, the flow resistance of the connected hot air system must be reduced.
Air Top 2000 ST Servicing work Plastic tank Sealing ring l1 + l2 ≤ 10 m l1 ≤ 1.2 m l2 ≤ 8.8 m Fig. 803 Fuel extractor from the plastic tank (extraction through tank drain screw) Fuel standpipe Fig. 801 Fuel supply Sealing ring Hole pattern 25 > 25 mm Tank fitting NOTE Only use a tank extractor with metal fuel tanks Fig. 802 Webasto tank connector NOTE The fitting must be made from metal! Fig.
Servicing work Air Top 2000 ST 8.6.2.2 Fuel lines Air Top 2000 ST 12 V - petrol Only steel, copper and plastic lines of plasticised, light and temperature-stabilised PA11 or PA12 (e.g. Mecanyl RWTL) pursuant to DIN 73378 may be used for the fuel lines. Since the lines normally cannot be routed with a constant rising gradient, the internal diameter must not be allowed to exceed a certain size.
Air Top 2000 ST 8.6.5 Combustion air supply Under no circumstances may the combustion air be taken from areas occupied by people. The combustion air intake opening must not point in the direction of travel. It must be located so that it cannot become clogged with dirt. NOTE The combustion air must be extracted using a combustion air line from a position that is as cool as possible and protected from splashing water for petrol heaters.
Servicing work 8.6.8 Electrical connections 8.6.8.1 Heater connection, control element Air Top 2000 ST The wiring harness is prepared for connection to the control element (setpoint generator). Simply pull on connector housing to unplug the connector (Fig. 813). The electrical connection is to be made as shown in the appropriate circuit diagram (see section 7). To connect the wiring harness, remove the cover (see 9.2.1.1) on the heater and connect the wiring harness plug to the control unit.
Air Top 2000 ST Servicing work 1 2 3 4 5 6 7 Control element Heater Metering pump and damper Fuel filter (accessory) Tank connector Exhaust silencer Fuse Fig.
Servicing work 8.7 Removal and installation IMPORTANT When the heater is installed it must not be dismantled. 8.7.1 Heater, removal and installation 8.7.1.1 Removal 1. Disconnect the battery. 2. Pull the cover off the top shell as described in 9.2.1.1 3. Disconnect the wiring harness plug from the control unit. 4. Disconnect the cable to the metering pump at the disconnection point. 5. If necessary disconnect the hot air hose or hoses connection. 6.
Air Top 2000 ST 9 Repair 9.1 General This section describes the repair work that may be carried out on the Air Top 2000 ST heater after it has been removed from the vehicle. Any further dismantling will invalidate the warranty. Only use the spare parts from the appropriate spare parts kits for assembling the heater. 9.1.1 Work on stripped down components IMPORTANT All sealing elements between the stripped down components and the seal on the exhaust outlet must always be discarded and replaced.
Repair 9.2 Dismantling and assembling 9.2.1 Remove the casing parts 9.2.1.1 Cover for electrical connection The cover (1,Fig. 902) can be carefully levered off using a blunt blade in the areas marked X . 9.2.1.2 Grille for hot air inlet and outlet The grille (5) can be released from its mounting by twisting it and then pulled off forwards. 9.2.1.3 Cover for hot air inlet and outlet Both covers (3 and 6, Fig.
Air Top 2000 ST Repair . 1 2 3 5 6 4 5 1 2 3 4 5 6 7 Cover, electrical connection Top shell Cover, hot air outlet Bottom shell Grille Cover, hot air inlet Insulators 7 Insulator positioning Insulator Widening of corner rib Fig.
Repair Air Top 2000 ST 9.2.3 Replace control unit 9.2.3.1 Removal 1. 2. 3. 4. Remove heater (see 8.7.1.1). Remove casing parts (see 9.2.1). Spread apart the lock of the hot air blower. Pull the hot air blower (1, Fig. 903) off the motor shaft by hand. 5. Disconnect plug connections on control unit (3). 6. Remove screws (2) and control unit (3). 7. Complete work on stripped down components (see 9.1.1). NOTE Do not carry out any repair work to the control unit. 3.
Air Top 2000 ST Repair 9.2.6 Replace flame sensor (petrol heater only) 9.2.6.1 Removal 1. 2. 3. 4. 5. 6. 7. 8. 9. Remove the heater (see 8.7.1.1). Remove the casing parts (see 9.2.1). Remove the control unit (see 9.2.3.1). Remove the combustion air fan (see 9.2.5.1). Remove the two screws (2, Fig. 903) and the air baffle (3). Press the cable grommet (11) on the flame sensor connection cable out of the heat exchanger (9) to the inside.
Repair Air Top 2000 ST 9 Detail A 7 6 5 4 8 3 2 1 1 2 3 4 5 6 7 8 9 Hot air blower Torx screw (3) Control unit Torx screw (5) Combustion air fan (drive) Seal Heat exchanger Overheating sensor Insulator (4) Fig.
Air Top 2000 ST 9.2.7 Change glow plug 9.2.7.1 Removal 1. 2. 3. 4. 5. Remove the heater (see 8.7.1.1). Remove the casing parts (see 9.2.1). Remove the control unit (see 9.2.3.1). Remove the combustion air fan (see 9.2.5.1). Press the cable grommet (10, Fig. 904) out of the heat exchanger (9) toward the inside. 6. Remove the four screws (2) and the air baffle (3). NOTE Check the burner insert (5) has detached from the combustion pipe (13). 7. Carefully pull out the burner insert (5) by tilting. Repair 5.
Repair Air Top 2000 ST 6 5 4 3 7 9 2 8 1 10 11 12 13 1 2 3 4 5 6 7 Flame sensor (only petrol heater) Torx screw (4) Air baffle Securing strap Burner insert Glow plug Screw 8 9 10 11 12 13 Grommet Heat exchanger Cable grommet Cable grommet (only petrol heater) Seal Combustion chamber Fig.
Air Top 2000 ST Repair 9.2.8 Change burner insert, combustion pipe and heat exchanger 9.2.8.1 Removal 1. 2. 3. 4. 5. 6. Remove the heater (see 8.7.1.1). Remove the casing parts (see 9.2.1). Remove the control unit (see 9.2.3.1). Remove the overheating sensor (see 9.2.4.1). Remove the combustion air fan (see 9.2.5.1). Remove the flame sensor (only petrol heater) (see 9.2.6.1). 7. Remove the glow plug (see 9.2.7.1). IMPORTANT In the following procedure make sure that the fuel connection is not bent. 8.
Repair Air Top 2000 ST Starting air hole Fig.
Air Top 2000 ST 10 Packing, Storage and Shipping Packing, Storage and Shipping 10.1 General If the heater or its components are sent to Webasto AG for testing or repair, it must be cleaned and packed in such a way that it is protected against damage during handling, transport and storage. An ambient temperature of +85 °C or –40 °C must not be exceeded for storage. Shipment address: For details please contact your Webasto representative.
Packing, Storage and Shipping Page for notes 1002 Air Top 2000 ST
National: Hotline: 01805 93 22 78 (€ 0,14 aus dem deutschen Festnetz) Hotfax: 0395 5592 353 Hotmail: technikcenter@webasto.com www.webasto.de International: www.webasto.com Ident-No.
