Hydraulic installation
20
Installation and maintenance instructions ecoTEC pro 0020129672_03
6
6
Hydraulic installation
The work described in this section must only be carried out
by a competent person.
6.1
Preparing for installation
a
Danger!
Risk of death caused by an incorrectly
installed system!
Heating water that leaks from the discharge
pipe of the expansion relief valve can cause
severe burns.
>
Install the expansion relief valve and the
opening for the drain line in such a way
that there is no danger to any persons in
or around the building. This may be out-
side or to a suitable open drain in the
installation room.
>
Make sure that the drain is visible.
b
Caution.
Risk of damage caused by contaminated
lines.
Foreign bodies such as welding remnants,
sealing residue or dirt in the water pipes
can cause damage to the boiler.
>
Flush the heating installation thoroughly
prior to installation.
b
Caution.
Risk of damage from corrosion.
If non-diffusion-tight plastic pipes are used
in the heating installation, this may cause
air to enter the heating water and corrosion
of the heat generation circuit and the
boiler.
>
If using non-diffusion-tight plastic pipes
in the heating installation, separate the
system by installing an external heat
exchanger between the boiler and the
heating installation.
a
Danger!
Risk of scalding and/or damage due to
incorrect installation leading to leaking
water.
Stresses in the supply line can cause leaks.
>
Make sure there are no stresses in the
supply lines when they are installed.
b
Caution.
Risk of damage caused by heat transfer
when soldering.
Heat that is transferred during soldering
can cause damage to the seals in the serv-
ice valves.
>
Do not solder the connection pieces if
the connection pieces are screwed to the
service valves.
i
Seals made of rubber-like materials may be sub-
ject to plastic deformation, which can lead to
pressure losses. We recommend using seals
made of a paste-like fibre material.
The Vaillant ecoTEC boiler is equipped with an 8 l expan-
sion vessel with a gas-side filling pressure of 0.075 MPa
(0.75 bar), which is suitable for a closed heating system
with a maximum water volume of 80 litres.
>
Before installing the boiler, check whether the volume of
the installed expansion vessel is sufficient.
>
If the volume of the expansion vessel is insufficient, then
install an additional expansion vessel connected as close
to the boiler as possible into the boiler return pipe.
i
When using an external expansion vessel
together with a VUW boiler, it is advisable to
install a non-return valve in the outlet (boiler
flow) or take the internal expansion vessel out of
service.
Otherwise, the warm start function may be more
frequently activated because of backflow, which
causes unnecessary energy loss.
Vessel volume
(in l)
Initial system pressure (in bar)
1.0
1.5
Expansion relief valve setting
(in MPa (bar))
0.3 (3.0)
With system volumes greater than 80 l,
multiply the volume by the adjacent factor.
0.109
0.156
6.1 Size of an additional expansion vessel
