Webasto Air Top 2000 STC User manual

Air Top Installation Guide
Air Top 2000 STC
Air Top EVO 40
Air Top EVO 55
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Webasto Air Top Installation Guide
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General Information
Webasto Thermo & Comfort Australia Pty Ltd is pleased to provide this installation guide for the Air Top heating
system. When used according to the guidelines stated in this booklet, you should expect many years of trouble-free,
enjoyable operation.
This installation guide represents our latest effort to produce the best technical documentation possible. In our
efforts toward continuous, ongoing product improvement, we also encourage our customers to provide feedback
concerning this guide and the Air Top heating system.
Visit our website for technical documents: www.webasto.com
This Webasto Diesel Heater comes with a 2 year warranty.
Failure to follow these installation instructions and the notes contained therein will lead to all warranty being refused
by Webasto Thermo & Comfort Australia Ltd Pty . The same applies if the repairs are carried out incorrectly or with
use of parts other than genuine Webasto service parts. This will result in the voiding of all warranty. All service and
repairs have to be carried out by authorised Webasto service dealers.
Note: In case of warranty situations, the serial number will be requested by Webasto or an authorised dealer to
validate.
Purpose of the Air Top Heater
The Webasto Air Top heaters are designed to heat the cabins of boats, trucks, minibus’, vans, motorhomes, caravans
and camper trailers.
The air heaters operate independently of the engine and are connected to either the vehicle’s own fuel tank or via a
separate fuel tank and the electrical system of the vehicle.
They are not designed to heat hazardous substances.
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Pre-Installation Considerations
1) Location and orientation of the heater.
The heater may be fitted to the interior or exterior of the vehicle. If it is installed externally, ensure that the heater is fitted in
a position where it is protected from water and dust ingress.
2) Length of hot air outlet ducting – the shorter, the better. Ensure that the hot air outlet is not directed towards or
in contact with the human body, as the hot air temperature can range from 80-120oC.
3) Return air vent - in some cases where there is enough air circulation in and around the heater, ducting may not
be required to the return air vent. Where it is required, keep ducting to a minimum.
4) Location of the controller, electrical wiring, fuse and battery connections.
5) Location of the fuel pump and fuel filter.
6) Location of the exhaust system. Ensure that the exhaust is not facing direction of travel.
7) Location of the combustion air systems.
8) Fuel pick-up options – 12L Webasto fuel tank or standpipe.
9) Electrical - ensure to use the supplied fuses in the kit and battery positive and negative connected directly to the
house battery.
Tips
Loosely attach the heater with the mounting bracket and place it in your desired location to predetermine the heater
orientation, ducting layout, airflow, wiring, controller and general clearance for easy accessibility and for future
service and repair.
Serial Number Labelling
Ensure that the serial number labels are attached on the top or the side of the heater in case the heater is mounted
against a wall and the original label may be inaccessible. Additional labels are supplied in the kit and one should go
on the installation manual envelope to hand over to the customer at the time of commissioning.
Note: In case of warranty situations, the serial number will be requested by Webasto or an authorised dealer to
validate.
Fig 1 – Serial number labels – Heater
Fig 2 – Serial number label written
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1 Technical Details
1.1 Heater Dimensions – Air Top 2000STC
Note: All dimensions in millimetres
1 Heating Air Inlet
5 Fuel Inlet
2 Heating Air Outlet
6 Space Requirement for Heating Air Inlet
3 Combustion Air Inlet
7 Space Requirement for Installation & Removal of Heater
4 Exhaust Gas Outlet
8 Cable Outlet (Optional Right or Left)
1.2 Heater Dimensions – Air Top EVO40/55
Note: All dimensions in millimetres
1 Heating Air Inlet
A Space Requirement for Heating Air Outlet
2 Heating Air Outlet
B Space Requirement for Heating Air Inlet
3 Combustion Air Inlet
C Space Requirement for Installation & Removal of Heater
4 Exhaust Gas Outlet
6 Cable Outlet (Optional Right or Left)
5 Fuel Inlet
Fig 3
1
2
3
4
5
6
Fig 4
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1.3 Technical Data
Model Overview Air Top 2000STC Air Top EVO 40 Air Top EVO 55
Voltage (V) 12 24 12 24 12 24
Fuel Type Diesel Diesel Diesel
Heat Output (kW)
Partial Load - Full
Load/Boost
0.9 - 2.0 1.5 – 3.5 / 4.0 1.5 – 5.0 / 5.5
Fuel Consumption (L / hr)
Partial Load - Full
Load/Boost
0.12 - 0.24 0.18 – 0.43 / 0.49 0.18 – 0.61 / 0.67
Power Consumption (W)
Partial Load - Full
Load/Boost
14 - 29 15 – 40 / 55 15 – 95 / 130
Dimensions (LxWxH mm)
Weight (kg)
311 x 120 x 121
2.6
423 x 148 x 162
5.9
423 x 148 x 162
5.9
1.4 Floor Mounting Bracket
Fig 5 - Floor bracket with 140mm OD diameter flange
50mm
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2 Step by Step Installation
1. After checking what is under the floor to ensure clearance of tanks, chassis rails etc., Drill the 140mm floor
mount bracket cut out.
2. Assembly of the heater
2.1 Assemble the heater to the bracket with the rubber gasket using the 10mm nuts and washers supplied in the
kit.
(Rubber gasket must be applied to avoid any heat distribution through the vehicle floor)
2.2 Place the heater so that the bracket is facing up (Fig 8), you will now notice electrical wires bundled in the
combustion air inlet, the 2 black wires are for the fuel pump.
Fig 7
Fig 6
Fig 8 – Bracket facing upwards and notice the wires in the combustion air inlet.
The seal gasket must be replaced each time the heater is removed and reinstalled.
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2.3 The combustion air inlet has a slot to accommodate the wires, ensure the fuel pump wires sit neatly in this
slot. Never run the wires through the combustion air inlet tube as it will create air restrictions.
2.4 Attaching combustion air tube. A matching slot needs to be cut in one end of the combustion air tube to
accommodate the fuel pump wires.
2.5 Using the hose clamp, fix the combustion air tube to the inlet.
Note: Ensure that the hose clamp & fuel pump wires are not rubbing.
Under no circumstance should the combustion air be taken from inside the cabin area. 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 or
road debris.
The combustion air must be extracted using a combustion air tube supplied in the kit and protected from dust and
water ingress.
Fig 9
Fig 10 – Combustion Air Tube “V”
Fig 10a – Combustion Air Filter
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2.6 Attach the fuel line using the 10mm hose clamp & rubber fuel line connector, fix to the fuel inlet, then fix the
fuel line to the open end of the rubber connector and secure with another 10mm hose clamp. (Ref: Fig 9).
2.7 Install the stainless-steel exhaust pipe, using the exhaust clamp to the exhaust gas outlet.
The exhaust pipe temperature is above 250oC. Ensure that the end cap is properly mounted and pointing downwards
(fig 12.1). The exhaust must not point in the direction of travel. The exhaust must be secured and away from heat
sensitive components, vehicle fuel lines and harnesses. Webasto can supply exhaust lagging if required.
Fig 12 – The exhaust or combustion pipe must be located so
that they cannot be clogged by dirt or road debris
Fig 11 an exhaust muffler is
supplied in the kit.
Fig 12.1 – Ensure that the end cap is properly mounted
and pointing downwards on the exhaust pipe.
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3Electrical System
3.1 Main Harness – Air Top 2000STC
Do not cut or extend the controller wiring harness. This will void the warranty. If an extension is required for the
control element plug (Fig 13) (X9), an extension harness is available from Webasto.
We only recommend extending the battery positive (red) and negative (brown) wires. Correct wire size of 6mm to be
used to avoid any current or voltage drop in the circuit.
Ensure that the main plug is properly “home” in the ECU (Fig 13) (3). The main positive (red) and negative (brown)
must be directly connected to the house battery and NOT via a master switch to ensure correct shut down cycle of
the heater.
Number
Function
1
Fuse Holder
2
Red Wire (Battery Positive)
3
Main Plug
4
Brown Wire (Battery Negative)
5
620 Ohm Resistor
6
Rotary Controller (Potentiometer)
7
Multi-control digital
Fig 13 – Air Top 2000STC Main Harness connections
1
2
3
4
5
6
7
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3.2 620 Ohm Resistor – Air Top 2000STC Only
Please note –The black wire with blue stripes, with the mini spade terminals - labelled as ‘temperature sensor’, must
be connected to the 620 Ωresistor which is supplied in the kit. Polarity does not matter. If the resistor is not
connected when using the multi-controller the error code F94 will appear. Otherwise, if using the dial controller and
the resistor is not connected the error code F06 will occur.
NOTE: The 620ohm resistor is does not need to be exposed as it is not the temperature sensor.
3.3 Extension Harness for Controller
Where an extension harness is required for either the rotary or digital multi-control a 1.8m or 6m standard extension
is available. Due to the plug location on the EVO 40 / 55 main harness, a 1.8m extension may be supplied in the kit.
Connect 620 Ω resistor
to wires marked
‘Temperature Sensor’
620 Ω resistor supplied
loose & in a separate pack
within the kit.
Fig 15 – 1.8m or 6m extension harness for controller
Fig 14 – Air Top 2000STC 620 Ohm connection
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3.4 Main Harness – Air Top EVO 40 / 55
Do not cut or extend the controller wiring harness. This will void the warranty. If an extension is required for the
control element plug (Fig 16), an extension harness is available from Webasto.
We only recommend extending the battery positive (red) and negative (brown) wires. Correct wire size of 6mm to be
used to avoid any current or voltage drop in the circuit.
Ensure that the main plug is properly “home” in the ECU (Fig 16) (3). The main positive (red) and negative (brown)
must be directly connected to the house battery and NOT via a master switch to ensure correct shut down cycle of
the heater.
Number
Function
1
Fuse Holder
2
Red Wire (Battery Positive)
3
Main Plug
4
Brown Wire (Battery Negative)
5
Rotary Controller (Potentiometer)
6
Multi-control digital
Fig 16 – EVO 40 / 55 Main Harness connections
1
2
3
4
5
6
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3.5 Fuses Holder
The Air Top requires 6-7 amps during start-up. The main power connection must be made at a circuit designed to sustain this
load without any voltage or current draw. Auxiliary vehicle power outputs for any other electronic accessories are not
considered adequate for the power supply for the heater.
If any battery management system is used, please contact a Webasto authorised dealer to ensure correct shutdown cycle is
maintained and prevent carbon build up.
3.6 Fuel pump Wiring
A 7m fuel pump harness (Fig 18) is supplied in the kit to connect to the fuel pump. Blue and brown, twin core
harness connects to the two black wires out of the combustion air inlet. Polarity does NOT matter. Plug kits
are supplied; spade terminals or standard automotive electrical connections can be used.
Note: Never run the wires through the combustion air inlet tube, as it will create air restrictions. Ref: Section
2 – (2.4 & 2.5)
3.5 Installation of Control Element
Install the control element in a convenient location. The control element does not measure temperature. The
monitoring of temperature is registered via a return air temperature sensor located inside the heater.
Fig 18 – Fuel pump wiring harness
Fig 21 – Rotary Controller
Fig 20 – Multi Controller –
complete with mounting kit
Fig 19 – Wiring to the fuel pump
Fig 17 – Fuse holder and fuses supplied in the kit.
F1 = 20A for Heater - 12V Heater
F1 = 15A for Heater - 24V Heater
F2 = 1A for Multi-Controller
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4 Fuel Systems
For caravans, Webasto can supply a 12L plastic fuel tank with sight level gauge and a quick connect for the fuel line.
With Motorhomes, fuel can be sourced out of the vehicle’s own fuel tank via a fuel pick up supplied with the kit.
Note: When sourcing fuel from vehicle’s fuel tank, do not cut into the return or supply line for two reasons:
1. Latest model vehicles have highly pressurized fuel systems.
2. If you perform any modifications to the vehicle, you may void the vehicle warranty.
Ensure that the clamps are tight on the fuel filter and the fuel pump and follow the direction of the flow as shown by
arrows on the fuel filter and the fuel pump for correct operation. The fuel lines can be protected in conduit and cable
ties to secure; these are not supplied in the kit.
4.1 Installation – Fuel Pump
Ensure that the fuel pump is installed with the clamp, 90oelbow and the rubber mounting bracket supplied in the kit.
This will reduce resonation through the vehicle. (Fig 23)
Fig 22 – Sample fuel system layout with Webasto 12L plastic fuel and vehicle fuel tank.
Fig 23 Fuel pump installed
with rubber mounting
bracket (below)
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4.2 Installation of Fuel Stand Pipe
Please Note: depending on the OE vehicle manufacturer, it could be possible to void vehicle
warranty if you amend or alter the original OE system, please ensure you check with the
manufacturer (dealer) prior to commencing any work.
When fuel is sourced out of the vehicle’s fuel tank, ensure that the stand pipe is installed on a flat surface and cut
the stand pipe length so that it is 25mm from the bottom of the tank.
Install the tank extracting device as shown (Fig 24)
Shorten the immersion tube; the end should be approx. 25 mm off the bottom of the tank. Cut the tube diagonally
and ensure you deburr the cut edges. (Fig 24)
Drill a 25mm hole on the flat surface of the tank (Fig 25). Ensure you grease the drill bit and drilling surface or apply
masking tape beforehand (to catch small drilling chips or swarf entering the fuel tank).
Install the fuel pick up and tighten the locking nut (the seal should be slightly compressed; applying any locking glue
will be advisable).
For vehicle specific installation details per refer to the vehicle manufacturer.
In case you are not able to use the stand pipe shown Fig 24 (Top mount type), Webasto can supply another option
(Fig 26 bottom mount type).
4.3 Factory Auxiliary Fuel Pick Up
Fig 24 – Installing fuel extracting device – (Top Mount type)
Fig 25 – 25mm - Fuel Extracting Device
Fig 26 – Installing fuel extracting device - Bottom Mount
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On some motor-home vehicle chassis’ a factory auxiliary fuel pick up is supplied however does not have the
extraction tube going to the bottom of the tank. Webasto can supply the correct parts & fittings (Fig 24) to suit.
Ensure the fuel extraction tube is cut at 45oas shown below.
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4.4 Fuel Filter
To ensure a clean combustion process, a fuel filter is supplied. Always check the direction of flow as marked on the
filter (Fig 27). The filter should be installed between the fuel source and the fuel pump.
Do not substitute the Webasto supplied fuel filter with non Webasto replacement.
4.5 Fuel Line
Only Webasto supplied Fuel Line should be used for the fuel delivery to the heater. Use of any other fuel line will
result in malfunction of the heater and will void warranty. To ensure correct connections, rubber hose connectors,
10 mm hose clamps and fuel line are supplied in the kit.
Fig 27 – Webasto Genuine fuel filter
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5 Ducting Layouts
5.1 Sample One Outlet layout
5.2 Sample Twin/Multi Outlet Layouts
Ensure that the hot air and return air outlets are at least 1m away from each other or located in different directions
to avoid any short cycle. Any short cycle in the system will affect the performance of the heater.
COMPONENT
DESCRIPTION
1
RETURN AIR
2
Y-JUNCTION
3
HOT AIR OUTLETS
Fig 30
Fig 29
Fig 28
Return Air
Return Air
Fig 29a & b
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6 Enclosing the heater
1) Ensure that the area around the heater is not jam packed while using the compartment as storage as the
heater itself and any ducting will get hot (70-80oC).
2) Heater can be boxed but it is recommended to have some breathing holes or grills on the enclosure to allow
air flow in and around the heater.
3) The ducting must be secured and ensure it cannot be crushed.
4) Ensure the ducting connections are properly secured by the clamps supplied in the kit.
5) In cases where no return air duct has been applied, ensure you install the open grill to the return (heating)
air side of the heater as supplied in the kit.
At no point should a hot vent be located or directed towards a person or areas where people are sitting. Hot air
outlet temperature can be between 80o-120oC.
The heat SHOULD BE directed away from all body parts.
7 Starting the Heater for the First Time
1) Ensure all ducting is connected and secured.
2) Ensure all fuel connections and clamps are connected and secured.
3) Ensure sufficient fuel is available from your fuel source.
4) Ensure that the battery connections are connected and secured.
5) Ensure the supplied fuse has been installed. (Check amperage).
6) Turn the heater to 100% or MAX.
7) Ensure you bleed the fuel system. (See Fuel line bleeding tip).
8) It will take at least 5 mins before you will experience hot air out of the hot air vents.
9) Leave the heater running for at least an hour.
7.1 Start-up Sequence
The glow plug and the combustion air fan start the operation and combustion process (audible combustion sound of
the combustion air fan and the ticking of the fuel pump will be noticeable). The fuel will be delivered and the
combustion air fan speed will accelerate and provide hot air.
7.2 Switching Off
When heating is no longer required, switch the heater off by the means of the controller on the heater. Never turn
the heater off by the main power supply.
The combustion will be extinguished, followed by a shutdown cooling cycle.
7.3 Fuel Line Bleeding Tip
Turn the heater on with the start-up sequence and the process of the fuel pump will operate. During this operation
fuel will be delivered to the heater. Depending on the length of the fuel line this may take a few attempts.
During the process the heater will try to start twice and if the fuel has not been delivered, it will show a fault code of
F01 - No start (after 2 attempts to start).
You will need to reset the heater by following the reset procedure – see Page 20, Section 9.
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8 Basic Layout of Complete Installation
9 Reset Procedures
Rotary Control (for multi-control please refer to page 30, error code H07)
When the controller starts to flash, disconnect the power supply to the heater by:
1) Whilst the controller is in the on position & code flashing, remove the fuse (15A) or disconnect power to the
heater
2) Turn the dial switch to off
3) Wait for a few minutes
4) Re-install the fuse
5) Restart the heater
COMPONENT
DESCRIPTION
COMPONENT
DESCRIPTION
1
CONTROLLER
8
FUEL STANDPIPE
2
INTERFACE VEHICLE HARNESS
9
FUEL TANK
3
HEATER FUSES – F1 (15A) &
F2 (10A) {Fig. 17 Pg 12}
10
FUEL LINE
4
HOT AIR OUTLET
11
EXHAUST PIPE
5
HOT AIR OUTLET DUCT
12
COMBUSTION AIR INTAKE PIPE
6
FUEL PUMP
13
RETURN (HEATING) AIR INTAKE
GRILL
7
FUEL FILTER
Fig 29 – Basic Complete Installation Layout
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