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Installation and maintenance manual ecoMAX 646
4.4 Gas
connection
Caution!
Ensure the gas line is disconnected from the
power supply when mounting it so that no leaks
are caused.
Caution!
The checking of the gas ducts for leaks may
only be carried out with a maximum pressure of
50 mbar, since otherwise the gas valve might
get damaged.
The appliance must be connected to your gas line via a
gas ball cock with a fire protection apparatus.
• Screw the appliance‘s gas supply pipe (1) gas-tight with
the (pre-installed) gas ball cock (2). To do this, use the
R3/4 compression fitting supplied with the appliance.
This is suitable for the connection of a R3/4 gas ball
cock.
• Inspect the gas connection for leakage.
2
1
Fig. 4.6 Gas connection (only surface installation possible)
4.5 Heating
side
connection
Caution!
Ensure the connecting cables are disconnected
from the power supply when mounting them so
that no leaks are caused in the heating system.
The appliance is connected to the heating supply and re-
turn via maintenance cocks. An installation set for the
ecoMAX 646 is available (item no. 306 715).
Caution!
It is imperative that the filling device be mount-
ed in the return; otherwise, the bleeding of the
appliance is not guaranteed.
Note!
When using a cylinder, a gravity brake is to be
mounted in the supply.
• Screw in supply (3) and return (4) with the mainte-
nance cocks.
3
4
Fig. 4.7 Mounting the heating supply and return
4.6 Flue
pipe
Danger!
Only use original Vaillant flue pipes, since these
are authorized together with the boiler. Mal-
functions can occur if you use other accesso-
ries. These may result in damage and injury.
X
*
Fig. 4.8 Mounting example - vertical roof duct
* In case of x > 1 m an inspection hole has to be provided
Installation 4
