Webasto Air Top Evo 3900/5500 B, Руководство по установке, Страница: 16 / 36

Webasto Product N.A., Inc. 14 www.techwebasto.com
Fuel Supply Air Top Evo 3900/5500
6.2 Vehicles with Fuel Injection Engines
When installing the heater in a vehicle with fuel injection system, it is important to establish whether the fuel pump is
located inside or outside the tank.
If the fuel pump is located inside the tank, fuel can only be extracted from the return line using the Webasto fuel
extractor (see Figure 12), in which case it must be ensured that the return line continues almost to the bottom of the
tank (see Figure 13 for details of the minimum distance from the bottom of the tank). If this is not the case Webasto
fuel extractors or standpipes (see Figures 13, 14 and 15) may be used.
If the fuel pump is installed outside the tank, the fuel connection may also be made between the tank and the fuel
pump, again using only the Webasto fuel extractor (see Figure 12).
6.3 Vehicles with Diesel Engines
The fuel must be taken from the vehicle fuel tank or from a separate tank (see Figs. 13, 14 and 15). This separate fuel
pickup precludes any effect of pressure.
Figure 13. Webasto fuel standpipe
NOTE:
The tank fitting must be made from metal!
6.4 Fuel Lines
Only steel, copper and plastic lines 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 2 mm and
these will cause malfunctions whilst the heater is operating if the lines sag or are routed downwards. The diameters
specified in Figure 11 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 (exhaust line).
The fuel lines must be secure at the connections using hose clamps to prevent their slipping.
*
25
Minimum distance 25 mm (1 in.)
Only use this Standpipe on fuel
tanks constructed from metal
Hole pattern