Webasto HL 90 Owner's Manual - page 6
1 Introduction
HL 90
102
Heating Air System
Heating air intake openings must be arranged so that
under normal operating conditions exhaust fumes of the
vehicle engine or air heater are not likely to be expected.
Extracting combustion air from the vehicle interior is not
permissible.
Combustion Air Line
The combustion air required must be taken from the
exterior.
Within rooms accommodating persons, the combustion
air lines must not have more than four disconnects
and a splash-water protected exterior wall feedthrough.
The disconnects must be sealed in a way not to exceed
a leak rate of 200 l/h at an overpressure of 0.5 mbar.
The line including feedthrough, disconnects, material
and specific type must be described in the installation
instructions.
The line must require tools for installation and removal,
must be protected against damage, and must be shock-
proof.
Exhaust Line
Heaters must be designed to discharge the exhaust to
the exterior.
Exhaust pipes must be routed so that exhaust fumes are
unlikely to penetrate into the vehicle’s interior.
The function of any parts of the vehicle essential for its
operation must not be impaired. Condensate or water
penetrated must not be able to accumulate in the
exhaust line.
Drain holes are permissible; these must drain the fluid to
the exterior via lines sealed against the vehicle interior.
The exhaust line outlet is to be positioned to the top, to
the side, or in case of exhaust venting below the vehicle
floor, to the nearest possible location of the vehicle’s or
cockpit’s side or rear end.
In compartments accommodating persons, exhaust lines
must not have more than one disconnect and must have
a splash-water protected feedthrough in the exterior
wall/floor. For water, that has penetrated into the exhaust
line, the connection of a drain line with a metal-sealing
joint is permissible. The drain pipe must be routed sealed
through the exterior wall or the vehicle floor.
The heat exchanger, the exhaust line connected, as well
as the possible drain pipe must be sealed so that with an
overpressure of double the overpressure of the exhaust
having the maximum permissible exhaust line length – at
least however at an overpressure of 0.5 bar – a total leak
rate of 30 l/h is not exceeded.
The line including feedthrough, disconnects, material
and specific type must be described in the installation
instructions. The line must require tools for installation and
removal, must be protected against damage, and must be
shockproof.
Metal lines must be used. These may not heat to more
than 110° C should there be the possibility of contact
within the room interior. Protective devices against con-
tact may be fitted.
Combustion Air Inlet and Exhaust Outlet
During installations these ports for combustion air entry
and exhaust fume exit must be of such type, that a ball
with a diameter of 16 mm cannot be inserted.
Electrical lines, switch gear and control gear of the heater
must be located in the vehicle so that their proper function
cannot be impaired under normal operating conditions.
For the routing of fuel lines and the installation of
additional fuel tanks §§ 45 and 46 of the StVZO are to be
adhered to.
The most important regulations are: Fuel lines are to be
designed in such a way that they remain unaffected by
torsional stresses in the vehicle, engine movement and
the like. They must be protected against mechanical
damage.
Fuel-carrying parts are to be protected against excessive
heat and are to be arranged so that any dripping or
evaporating fuel can neither accumulate nor be ignited by
hot components or electrical equipment.
In busses, fuel lines and fuel tanks may be located neither
in the passenger area nor in the driver's compartment.
In these type of vehicles the fuel tanks must be located
such that they do not pose a direct hazard to the exits in
the event of a fire. Fuel supply must not be by means of
gravity or pressurization of the fuel tank.
1.4.2 General Safety Notes
The heater must not be installed in the passenger or
driver compartments of busses. Should the heater never-
theless be installed in such a compartment, the installa-
tion box must be sealed tight against the vehicle interior.
There must be sufficient ventilation of the installation box
from the exterior in order not to exceed a maximum
temperature of 40° C in the installation box. Excessive
temperatures may cause malfunctions.
The heaters are cleared for heating the passenger and
driver cabin in the fresh air mode of operation and for load
top compartments in the fresh air or circulation air mode
of operation. They are however not cleared for heating
loading compartments for dangerous goods. The installa-
tion in enclosed areas accommodating persons is not
permitted.
If an air heater is installed in a loading compartment for
circulation air mode of operation the inside of the entrance
door shall be labeled as follows: "With heater on no
personnel allowed in loading area with door closed."
The heaters HL 90 are marked with the word "Diesel"
on their identification plate. The heaters may only be
operated with the specified type of Diesel (or with fuel oil
EL) and the appropriate type of electrical installation.