Install Instructions

IM-MP 724992 0117
12
3.5 Welding requirements
The following requirements must be considered
when welding in the same vicinity as Viega
MegaPress fittings.
3.5.1 Welding adjacent to Viega MegaPress fittings
When welding adjacent to a Viega MegaPress
connection, the installer must remain 4" away
from the connection to prevent damage to the
sealing element. The installer should take the
following precautions to keep the Viega MegaPress
connection cool while welding:
• Wrapping the connection with a cold, wet rag
• Protecting the connection with a weld blanket
• Fabricating weld connections prior to installing
the pressed fitting, making sure the pipe has
cooled before installing the fitting
• Consistently applying “spray type” spot freezing
3.5.2 Welding in line with Viega MegaPress fittings
When welding in line with Viega MegaPress fittings,
the installer must remain a minimum of three
feet away from the Viega MegaPress connection
to prevent damage to the sealing element. The
installer should take the following precautions to
keep the Viega MegaPress connection cool while
welding:
• Wrapping the connection with a cold, wet rag
• Protecting the connection with a weld blanket
• Fabricating weld connections prior to installing
the pressed fitting, making sure the pipe has
cooled before installing the fitting
• Consistently applying “spray type” spot freezing
3.6 General installation requirements
The Viega MegaPress fitting system must be
installed while considering the following general
industry requirements.
3.6.1 Expansion
Thermal expansion in installed systems generates
stresses in pipes and appliance connectors.
Compensation must be allowed for expansion
and contraction that may occur within the piping
system. Expansion joints or mechanical expansion
compensators may be used to alleviate these
stresses.
3.6.2 Electrical bonding
When properly installed, Viega MegaPress fittings
comply with Section 1211.15, Electrical Bonding
and Grounding, of the Uniform Plumbing Code and
Section 310 of the International Fuel Gas Code.
The mechanical press provides continuous
metal-to-metal contact between fitting and pipe.
The press ensures the continuity of the bonding
through this contact.
3.6.3 Piping exposed to freezing temperatures
In the Viega MegaPress system, the EPDM sealing
element can be installed in ambient temperatures
down to 0°F. The HNBR sealing element available
with Viega MegaPressG fittings can be installed
in ambient temperatures down to -40°F. Piping
systems exposed to freezing temperatures must
be protected per acceptable engineering practices,
codes and as required by the local authority.
3.6.4 Corrosion protection
Viega MegaPress fittings exposed to corrosive
action, such as soil conditions or moisture, must
be protected in an approved manner in accordance
with NFPA 54 section 404.8, NACE Standard
RP0169-2002 section 5, 2009 UPC Chapter 6
section 609.3.1, 2009 UMC Chapter 13 section
1312.1.3 and in a manner satisfactory to the local
code official.
Care should be taken to select hangers of suitable
material that is galvanically compatible with the
piping system. In addition, piping systems should
be properly sized to minimize the risk of erosion
corrosion resulting from excessive velocities.
3.6.5 Concealed spaces
Viega MegaPressG has been examined according
to the construction and performance criteria in the
CSA requirement LC-4 and was found acceptable.
Specific performance tests were conducted to
evaluate the fittings for use in concealed locations.
3.6.6 Underground installations
Viega MegaPress fitting systems and black iron
pipe are approved for underground installations.
However, any installations must meet all state and
local codes, including those for underground.
Proper authorization must be obtained prior to
underground installation from the local authority
having jurisdiction.
3.6.7 Pressure testing
The pressure testing of installed pipe is to be
completed in accordance with local codes or, in
the absence of local codes, in accordance with
NFPA 54 or NFPA 58.
3.6.8 Transition connections
Viega MegaPress system ½" to 2" can be joined
with off-the-shelf threaded fittings.
In this regard:
1. The threaded connection is made first.
2. The press connection is made second.
This process avoids unnecessary torsion.