Top-Mounted Valve Installation - Pentair FLECK 3150 NXT Installer Manual

Installer Manual Fleck 3150 - NXT - Installation

5.5.1. Top-mounted valve installation

The valve and tank should not be supporting any part of the piping weight. This is hence compulsory
to have the piping fixed to a rigid structure (e.g. frame, skid, wall...) so that the weight of it is not
applying any stress on the valve and tank.
• The diagrams above illustrate how the flexible piping connection should be mounted;
• in order to adequately compensate the tank elongation the flexible tubes must be installed
horizontally;
• should the flexible piping connection be installed in vertical position, instead of compensating
the elongation, it will create additional stresses on the valve & tank assembly. Therefore this is
to be avoided;
• the flexible piping connection must be also being installed stretched, avoiding excessive length.
For instance 20 - 40 cm is enough;
• excessively long and non-stretched flexible piping connection will create stresses on the valve
and tank assembly when the system is pressurized, as illustrated in the below picture: on the left
the assembly when the system is unpressurised, on the right the flexible piping connection when
put under pressure tends to lift up the valve when stretching up. This configuration is even more
dramatic when using semi-flexible piping;
• failure to provide enough vertical compensation may lead to different kinds of damage, either on
the valve thread which connect to the tank, or on the female thread connection of the tank that
connect to the valve. In some cases, damage may also be seen on the valve inlet and outlet
connections;
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Support to the wall
min 200 mm flexible
min 200 mm
flexible
Support to the wall
Ref. MKT-IM-010 / B - 28.05.2018