PEX Installation Manual

53
IM-PF 724596 0416
U-Type Expansion Offset (in)
per 50 linear feet of run
Tubing
∆T(°F)
Tube
nom.
60 80 100 120 140 160 180 200
L3 L4 L3 L4 L3 L4 L3 L4 L3 L4 L3 L4 L3 L4 L3 L4
ViegaPEX
&
ViegaPEX
Ultra
¾" 4.1 8.2 4.7 9.4 5.3 10.5 5.8 11.6 6.2 12.5 6.7 13.3 7.0 14.2 7.5 14.9
1" 4.6 9.3 5.3 10.7 6.0 12.0 6.6 13.1 7.1 14.2 7.6 15.1 8.0 16.0 8.5 16.9
1¼" 5.1 10.2 5.9 11.8 6.6 13.2 7.2 14.5 7.8 15.6 8.4 16.7 8.9 17.7 9.4 18.7
1½" 5.6 11.1 6.4 12.9 7.2 14.4 7.9 15.7 8.5 17.0 9.1 18.2 9.6 19.3 10.2 20.3
2" 6.4 12.7 7.4 14.7 8.2 16.4 9.0 18.0 9.7 19.5 10.4 20.8 11.0 22.1 11.6 23.2
The fastener shown on the L3 leg may be required to provide additional support depending on how the expansion loop is installed
(horizontal/vertical).
FostaPEX:
FostaPEX tubing has a fully dimensional PEX wall
with an additional outer layer of aluminum and
polyethylene. As a result of these extra layers,
FostaPEX expands considerably less than that of
standard PEX tubing and slightly more than copper
tubing (0.16" per 100' per 10°F).
An approved method for expansion absorption
when using FostaPEX is through the use of a coiled
loop expansion compensator (at least every 50
feet). Do not use fitting offsets with FostaPEX as
the stiffness of FostaPEX may lead to high stress
at connections.
Coiled loop:
The coiled loop configuration calls for loops within
the piping system. The diameter of the loop (D) is
shown in the table and will increase or decrease as
the tubing in the system expands and contracts.
Note: Tubing fasteners should be secured as to not
prevent linear movement of tubing.
Tube nom. D (in)
½" FostaPEX 12"
⅝" FostaPEX 14"
¾" FostaPEX 16"
1" FostaPEX 20"
D
Figure 16.4 Coiled Loop Expansion
Table 16.5 Coiled Loop Expansion