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HIU2-IM-DE-W-DE-08-2018-Rev1_DE-enUS | Art. No. 10078860
11
EN
ENGLISH
5 Installation and commissioning
Electricity!
Risk of death from electric shock.
• Work on parts carrying live voltage must
only be carried out by trained electricians.
• Disconnect the power supply of the sys-
tem and secure it against being switched
back on before carrying out any installa-
tion, maintenance, cleaning or repair work.
The installation and commissioning of the
HIU 2 must only be carried out by trained
personnel who have been authorized by
the manufacturer.
When installing and operating a circula-
tion system, the recognized rules of engi-
neering as well as the hygiene regulations
according to “DVGW Arbeitsblatt W551”
(German association for gas and water,
worksheet W551) must be observed.
The HIU 2 may only be installed in an
upright position.
When repairing the unit or replacing parts,
be sure to observe the specified installa-
tion positions and flow directions of the
parts being replaced.
Material damage!
Pressure shocks may occur if the stop
valve is opened quickly.
• Always open the stop valve slowly and in
a controlled way.
Bad water quality!
Hard water causes limescale deposits in
the HIU 2 and diminishes the quality of
the water.
• Measure the water hardness in the supply
system.
• Install a water softening unit from a degree
of hardness of 17° dH.
5.1 Installation
All screw fittings must be checked and tightened if nec-
essary prior to installation and commissioning.
Torque:
• ¾” screw fittings 35 Nm
• 1” screw fittings 55 Nm
Requirements
• The HIU 2 cabinet (surface-mounted or flush mounted) is
installed.
• A safety valve that cannot be shut off must be installed in
the cold water inlet to the HIU 2. In so doing, the acknowl-
edged rules of technology must be taken into account.
• The installation sequence must be observed to prevent
electrochemical corrosion of galvanized lines and fittings.
• The valves are pre-installed at the factory but must be
checked for leaks during commissioning (hydraulic pressure
test).
Recommendation: Install water filter into the cold
water inlet.