Wilo WEH, Installation And Operating Instructions Manual

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WILO SE 02/2014 5
English
tenance work. The installation should be freely
accessible from at least two sides.
The installation surface must be level and hori-
zontal.
7.2 Hydraulic connection
ATTENTION! Observe the requirements from
the water supply companies and the local rules
in force.
• Valves must be fitted on the manifolds to isolate
the pressure-maintaining system if required.
• The installation must be fitted with a diaphragm
pressure tank (Connection Fig. 5).
• The existing pipes must be installed free from
stresses.
Compensators with length limiters for flexible
connecting pipes are recommended for this pur-
pose in order to avoid stresses on the pipe con-
nections and minimise the transmission of install-
ation vibrations to the building installation.
For the horizontal versions with 1 and 2 pumps
The connection to the tank is done as follows
(Connection Fig. 5):
• Connection of the suction parts to the pumps
with union nut (within the scope of delivery).
• Connection of the suction parts to the tank with
union nut 1"1/4 (pos. 22).
• Connection of the overflow assembly and filter
to the tank with union nut 1" (pos. 23).
• Flexible connection to the pressure-maintaining
system with gasket (supplied in a plastic bag).
- Version 1 pump => connection to the 5 way
connector.
- Version 2 pumps => connection to the mani-
fold.
• Connection of the electrovalve 1" to the tank
(pos. 25) with union ½".
• Connection of the float switch (pos. 18) and fil-
ling ( pos. 17) to the tank.
• A drain valve 1" (pos. 26 is supplied with the
module.
• An overflow opening 1"1/4 (pos. 27) is available
and must be connected.
For horizontal version with 2 pumps
The connection of the discharge manifolds can be
made either on the right or left hand sides of the
installation. It is recommended to close the ports
that are not used with threaded caps.
For vertical version with 2 pumps
• The connection of the suction and discharge
manifolds can be made either on the right or left
hand sides of the installation. It is recommended
to close the ports that are not used with threa-
ded caps.
• A degassing connection (pos. 24 ) is connected
to the degassing assembly (pos. 28).
7.3 Electrical connection
WARNING! Risk of burn! Electrical shock hazard!
Electrical connections and checks must be per-
formed by an authorised electrician and according
to the standards in force.
To make the electrical connection, the corres-
ponding installation and operating instructions
and attached electrical circuit diagrams must be
observed. General points to be considered are
listed below:
• The type of current and voltage of the mains
connection must comply with the details on the
rating plate and the circuit diagram of the swit-
chgear.
• The electrical connecting cable must be adequa-
tely dimensioned according to the total power
of the pressure-maintaining system (see rating
plate).
• As a protection measure, the pressure-main-
taining system must be earthed according to
the rules (i.e according to the local regulations
and circumstances). The connections intended
for this purpose are identified accordingly (see
circuit diagram).
• The base frame has to be connected to earth by
using an earth braid linked to the frame.
7.4 Float switch
The electrical connection of the switches' float
level at the terminals of the switchgear is done in
the factory.
They are installed on the tank:
• Float switch against a low water level, for dry run
protection (pos. 18):
Place the float running protection in the tank so
that the system stops when the minimum water
level is reached, at least 10 cm above the drain
plug from the pump.
• Float filling (pos. 17):
Place the float filler in the tank so that the sys-
tem meets the water level when filling level is
reached.
8. Commissioning
We recommend that the pressure-maintaining
system is first commissioned by the nearest WILO
customer service agent or ask your central cus-
tomer service department.
8.1 General preparation and checking
• Before switching on the system for the first time,
check if the wiring has been done correctly on
site, particularly the earthing.
• Check if the pipe connections are stress-free.
• Fill the installation and check it visually for leaks.
• Open the shut-off valves on the pumps and in
the suction and discharge manifold.
• Loosen the pump vent screws and slowly fill the
pumps with water so that the air can escape
completely.
ATTENTION!
Do not allow the pump to run dry.
Dry running destroys the mechanical seal.
• Check the direction of rotation of the pump:
during a brief start, check whether the direction
of rotation of the pumps is the arrow on the label
on the pump. If the rotation is incorrect, interch-
ange two phases.
WARNING! Risk of burn! Electrical shock hazard
!
Switch off the installation's main switch before
changing the phases.
• Check if the motor heat protections inside the
switchgear are set for the right rated current. See