Wilo VBH Series, Installation And Operating Instructions Manual

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English
20 Wilo SE 07/2015
(maximum 180 s) which is defined at the control
device. If the water level in the tank rises again,
then the float switch will once again emit a signal
when the respective switching level is reached
(Fig. 7, upper position (13)). The system can then
afterwards be enabled by the regulator in the con-
trol device once again following the expiration of
a time delay (minimum 10 s).
CAUTION
! Low water in the tank can cause dry
running in the pressure boosting system. The
float switch integrated in the tank should be
connected to the control device in order to
avoid damage to the pressure boosting system
and/or to the pumps!
In the case of systems for fire extinguishing oper-
ation, fire prevention code stipulations may how-
ever prohibit the use of low-water signal
transmitters to switch off the pressure boosting
system in the event of fire. These stipulations will
take precedence in all cases!
7 Installation and electrical connection
7.1 Preparations for installation
The Wilo break tank is to be set up as close as pos-
sible to the pressure boosting system that is to be
connected to it. If any height compensation is
necessary, then a corresponding base pedestal
(Figs. 5a and 5b (31)) is to be set up. The following
basic prerequisites are to be complied without fail:
• The break tank should be set up in a well-venti-
lated, frost-free room.
• The installation surface must be horizontal and
flat. The baseplate of the tank must be supported
across its entire surface.
• The bearing surface must be able to bear suffi-
cient loads in terms of statics in order to ensure
that, at a minimum, the maximum filling quantity
can be supported safely.
• The break tank must remain accessible for main-
tenance work, even after the installation has been
completed. (at least 600 mm above the tank, 1000
mm at the operating side).
WARNING
! Danger of injury and danger of
damage to the tank.
The cover of the break tank cannot be walked
on! Non-permitted loads on the cover can lead
to destruction.
7.2 Hygiene
The Wilo break tank is in compliance with the valid
rules of technology and is designed for utilisation
with potable water applications. All of the materi-
als used are accordingly suitable for such applica-
tions.
Please take into account that when used and
operated in the potable water sector, the entire
potable water supply system needs to be handed
over to the operator in a perfect state of hygiene.
In addition, the obligations arising from statutes
(e.g. TrinkwV, AVBWasserV, etc.) and the recog-
nised rules of technology (e.g. DIN1988, VDI6023,
DIN EN1717, DIN EN 806, DVGW worksheets, etc.)
are also to be observed.
WARNING
! Contaminated potable water is a
health hazard!
• Flushing the pipes and the system reduces the
risk of affecting the quality of the potable
water!
• The water must be completely replaced after a
longer period of system standstill.
It is also to be ensured during operation that reg-
ular inspections of the state of hygiene and, when
necessary, mechanical cleaning and disinfection
are carried out. A suitable specialist company
should be called in for consultation in this connec-
tion or be issued a job order for the necessary
tasks.
7.3 Connecting the pressure boosting system
The connection between the break tank and the
pressure boosting system is set up at the draw-off
connection (3). It is absolutely necessary that the
connection be made stress-free in order to avoid
any damage caused by the transfer of mechanical
vibrations. Depending on the type and size of the
tank, and thus in accordance with the type of
draw-off connection being used, a flexible con-
nection line (Fig. 5a) or a compensator (Fig. 5b)
should be utilised for this purpose.
To avoid water losses, it is recommended that a
check valve be installed without fail between the
break tank and the pressure boosting system for
facilitating maintenance work.
7.4 Connection to the water supply network
The connection between the break tank and the
water supply network is accomplished by means
of an inlet valve which opens and closes in accord-
ance with water levels (accessory; to be ordered
separately). Depending on the type and size of the
tank, there are basically two different possible
versions available for use.
7.4.1 Float valve
In the case of tanks which are connected to and
fed from the potable water supply network by
means of a float valve (16), one or more lead-
throughs are provided for installation (see dimen-
sion sheets, Figs. 1a to h (1)). For the purpose of
installation (Fig. 3) with the connection thread of
the housing (16-4), the float valve is guided from
the inside through the tank opening provided for
this purpose and fixed in place from the outside
with the counter nut (16-3). The rods (16-4) and
the outlet opening of the float valve must face
downward. A detachable pipe union (17) and a
check valve (18) should be mounted downstream
from the float valve in order to ensure that the
water intake can be interrupted and that the valve
can be dismantled without difficulty if necessary.
A T-piece (19) is to be provided, particularly in the