Install Instructions

Fastening the Viega PureFlow System
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IM-PF 724596 1021 PureFlow Water System (EN)
12.4 Noise and Water Hammer in PureFlow Systems
As with all plumbing materials under some operating conditions, water
hammer can occur in PEX plumbing systems. The inherent 󶈶exibility
of Viega PureFlow PEX drastically reduces the magnitude of pressure
surges compared with metallic plumbing materials. Damage to plumbing
components in a PEX system due to these pressure surges is highly
unlikely, although noise can sometimes result. Fortunately, there are
solutions to minimize or eliminate water hammer noise.
■ Install 󶈵xtures that are not water hammer prone.
As a general rule, two-handle 󶈵xtures are less likely to cause hammer
than single-handle 󶈵xtures. Single-handle shower valves, which rotate
to close and therefore are di󶈷cult to close quickly, might be good
choices.
■ Clamping or strapping more frequently may help prevent tubing noise.
It is important that the tubing not be in contact with wallboard, forced
air ducts or other high-resonance articles. Insu󶈷ciently or improperly
clamped or strapped tubing may move during 󶈵xture operation and hit
against these surfaces.
■ Install a water hammer arrester at 󶈵xtures where noise is a problem.
A water hammer arrester (AA sized) installed as closely as possible
to the 󶈵xture on the cold-water side only will eliminate the source of
the noise (the pressure wave). It should be noted that even with an
arrester, tubing that is clamped or strapped insu󶈷ciently may still hit
against something as it moves slightly when the water 󶈶ow is stopped.
■ Avoid operating 󶈵xtures in such a way that causes near instantaneous
shuto󶈴. Simply closing 󶈵xtures in a less abrupt manner can eliminate
hammer noise.
12.5 Shower Valves
PEX lines should only be run to the inlet connections of tub/shower
valves unless speci󶈵cally approved by the valve manufacturer for other
connections.
12.6 Electrical Grounding
Viega PureFlow PEX tubing may not be used as an electrical ground.
Consult the NEC for recommended grounding method when plastic pipe
is used.