Gas Connection; Water Connection - Truma Combi 2 EAU Operating Instructions Manual

If the warm air duct has to be subjected to a considerable
amount of bending immediately behind the warm air outlet
of the unit in confined spaces, we recommend the use of
the BGC 90° elbow (part no. 34091-01). This elbow makes
it possible to connect a ÜR warm air duct with a diameter
of 65 mm or a VR warm air duct with a diameter of 72 mm.
Fig. 21
With a duct length of less than 2 m the air outlet must not
be installed higher than the warm air duct muff. With a duct
length of less than 50 cm, the duct must create a siphon be-
tween the connection and the outlet.
L ≤ 50 cm
Fig. 22
These measures prevent undesirable heating of the vehicle
due to convection (cowl effect) during operation in hot water
mode.
The ducts for warm air distribution must be firmly
inserted into the connections. A clip is attached to each
connection to provide a more secure grip.
For optimum warm air distribution, Truma always recommends
using the 4 warm air outlets of the heater. If only three warm
air outlets are needed, one of the lower warm air outlets must
be sealed with a blank cover VD-Combi (part no. 34310-01).
The blank cover must be firmly pushed into the moulded part
of the heater until it audibly engages and is firmly seated.
Check for firm seating.
If four warm air outlets are being used, a closable end
outlet EN may be installed in one warm air branch. If
there are only 3 warm air outlets, it must be ensured that if a
closable end outlet is being used (e.g. bathroom), a second
non-closable nozzle is installed in the warm air branch.

Gas connection

A gas pressure regulator has to be used, which en-
sures gas supply at gas pressure level 2.75 kPa. The
gas supply's operating pressure must be the same as the
unit's operating pressure (see type plate). The gas installa-
tion must comply with AS/NZS 5601.2.
The gas inlet connection on the Combi 2 E / 4 E (Australia) is a
8 mm connection.
Prior to connecting the appliance, make sure that the gas
lines are free from dirt, chips and such!
Gas-connection muff (21) on the unit may not be shortened or
bent.
Route the pipes in a way that will facilitate removing the unit
for service tasks.
To connect, the UNF 1/2" – 20 (SAE Male AN Flare) gas inlet
connection (20) provided with the appliance must be used.
The gas inlet connection is preinstalled. Carefully counterhold
with another spanner when tightening!
14
For connection to 8 mm steel piping Dometic provides an
adapter UNF 1/2" x RVS 8, part no. 70020-02700.
Fig. 23
Route the pipes in such a way that the appliance can be re-
moved again for servicing.
Refer to AS/NZS 5601.2 – Gas Installations, for gas pipe sizing.
It is mandatory that the tightness of the gas installation is
proved before starting up for the first time.
Check for gas leaks (do not check for gas leaks with a naked
L ≤ 50 cm
flame), then check that the gas pressure is as follows:
LPG: 2.75 kPa
Keep the number of separable connections in the gas supply
line in rooms frequented by people to a technically feasible
minimum.
The gas system must comply with the technical and adminis-
trative provisions of the individual country of use (in Australia,
AS/NZS 5601 for motor vehicles).

Water connection

For operating the water heater it is possible to use all pressure
pumps and submergible pumps up to 280 kPa, also all mixing
taps with or without electrical switch.
In order to guarantee complete emptying of the
water and to prevent pressures of greater than
450 kPa occurring in the hot water system, the en-
closed pressure reducer (18), the enclosed water con-
nectors (27 + 28) and the enclosed drain valve (24) must
be used!
When using pressure pumps with high switching hysteresis,
hot water may flow back through the cold water tap. To pre-
vent the backflow, we recommend that a non-return valve
(nrv – not included in the scope of supply) be fitted between
the outlet to the cold water tap and the drain valve.
Fig. 24
The supplied water connectors (27 + 28) and drain valve
(24) have a 12 mm rigid piping connection (e. g. John
Guest System). For connecting to rigid pipes with other diam-
eters appropriate adapters (not included in scope of delivery)
must be used.
Hoses with a diameter of 12 mm that are drinking water
compatible, pressure-resistant (up to 450 kPa) and hot water-
resistant up to +80 °C must be used to connect the unit and
the accessories. We recommend the use of John Guest pipes,
insertion sleeves and hose clamps.
20
21
28
26
nrv
24
29 27 25
23
18