Fuel Connection; Safety Instructions For Routing Fuel Lines; Installing The Metering Pump - Truma Combi D4 CP plus ready Einbauanweisung

Fuel connection

DIN EN 590-compliant diesel fuel is needed to operate the
heater.
The fuel is extracted from the vehicle fuel tank (see fuel tank
removal kit).
Extracting fuel from the return system of the vehicle
engine or downstream of the vehicle-internal delivery
pump is not permitted.
Please only use the fuel hoses and lines that are included in
the scope of delivery for installation.
Permissible fuel line length
The maximum fuel line length at the intake side is 2 m,
and 6 m at the pressure side.

Safety instructions for routing fuel lines

Always cut fuel hoses and lines to length using a hose cutter
(part no. 34020-45300) or a sharp knife. The areas that have
been cut must not be compressed and must be free of burrs.
Fuel lines must be securely attached in order to prevent dam-
age and / or noise generation caused by vibration (recom-
mended spacing between attachment points approx. 50 cm).
Fuel lines must be protected from mechanical damage.
Route fuel lines so that vehicle twisting, engine movements
and the like do not adversely affect the stability thereof.
Protect fuel-carrying parts from heat that may affect operation
(use suitable thermal protection hose made from fibre glass
fabric with aluminium lining).
Never route or secure fuel lines immediately adjacent to the
exhaust gas discharges of the heater or the vehicle engine.
If the lines cross, maintain an adequate distance away from
hot components – provide heat radiation protection panels if
necessary.
Do not leave gaps between fuel lines that are being con-
nected using a fuel hose. This prevents problematic bubble
formation.
Correct line routing
Erroneous line routing
(bubble formation)
Fig. 19
18

Installing the metering pump

Always install the metering pump (27) with the pressure side
(delivery direction) sloping upwards.
Protect metering pump (27) from heat (max. operating tem-
perature 40 °C), therefore do not install in the vicinity of sound
mufflers and exhaust ducts.
Metering pump installation position
Fig. 20
Permissible metering pump intake and pressure levels
Pressure level from fuel tank to metering
pump:
Intake level with depressurised fuel tank: b = max. 1000 mm
Intake level with fuel tank in which
negative pressure occurs during removal
(valve with 0.03 bar in tank cap):
Pressure level from metering pump to
heater:
a
b
Fig. 21
Attaching the metering pump
Attach metering pump (27) to vehicle in a suitable location
using bracket (28) and holder (29) (included in scope of
delivery).
90°
Fig. 22
a = max. 1500 mm
b = max. 400 mm
c = max. 2000 mm
c
28
27
29