Installation manual

www.webasto.us 21 Webasto Product N.A., Inc.
Thermo 90 S / Thermo 90 ST Fuel Supply
8.3 Fuel Lines
Only steel, copper and plastic lines made of plasticized,
light and temperature-stabilized PA 11 or PA 12 (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 or gas bubbles will
accumulate in lines with an internal diameter of more
than 4 mm (5/32 in.) and these will cause malfunctions
whilst the heater is operating if the lines sag or are
routed downwards. The diameters specified in Figure 17
will ensure that bubbles do not form.
The lines should not be routed downwards from the
metering pump to the heater.
Unsupported fuel lines must be secured to prevent them
from sagging. They must be installed in such a way that
they cannot be damaged by flying road debris and high
temperatures, i.e. close to the exhaust line.
The fuel lines must be secure at the connections using
hose clips to prevent their slipping.
IMPORTANT!
Cut lines without burr and do not crush
them. Do not cut fuel line with side cutting
pliers!
8.3.1 Connecting two fuel lines with a
coupler hose
The correct procedure for connecting fuel lines with
hosing is shown in Figure 23. Ensure that there are no
leaks.
Figure 23: Fuel line / coupler hose connection
8.4 Fuel Metering Pump
The fuel metering pump is a combined delivery, metering
and shut-off system and is subject to certain installation
criteria (see Figures 24 and 25).
Figure 24: Fuel metering pump DP2 - installation position
Figure 25: Fuel metering pump 30.2 - installation position
8.4.1 Installation Location
It is advisable to install the metering pump in a cool
place. The maximum ambient temperature must not
exceed +20 °C (68 °F) for gasoline heaters at any time
during operation.
The metering pump and fuel lines must not be installed
within range of the radiated heat from hot vehicle parts.
A heat shield must be used if necessary.
Clamp
Bubble
Bubble
Wrong
Correct
12 V and 24 V – Gasoline and Diesel (with damper)
12 V and 24 V – Diesel Only (with damper)
Horizontal Only!