Install Instructions

IM-PR 566442 1114 (Design Manual)

U-type expansion loop:

The U-type expansion loop integrates four 90° elbows that form a “U” pattern.

With this arrangement ⅕ of the “L” dimension is applied as the width (represented as L3) while ⅖ of “L” is

applied as each leg in the other dimension (represented as L4).

Calculate the necessary L3 and L4 dimensions or use the chart below, which was gured using the maxi-

mum run for a single expansion compensator (50 ft.).

L = 19.30"

L3 = ⅕ (L)

L3 = 19.30"/5 = 3.86"

L3 = 3.86"

L4 = ⅖ (L)

L4 = 2(19.30")/5 = 7.72"

L4 = 7.72"

U-Type Expansion Loop (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

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

ViegaPEX

Barrier

¾" 3.8 7.6 4.4 8.8 4.9 9.8 5.4 10.8 5.8 11.6 6.2 12.4 6.6 13.2 7.0 13.9

1" 4.3 8.6 5.0 10.0 5.6 11.2 6.1 12.2 6.6 13.2 7.1 14.1 7.5 15.0 7.9 15.8

1¼" 4.8 9.6 5.5 11.0 6.2 12.3 6.8 13.5 7.3 14.6 7.8 15.6 8.3 16.5 8.7 17.4

1½" 5.2 10.4 6.0 12.0 6.7 13.4 7.3 14.7 7.9 15.9 8.5 17.0 9.0 18.0 9.5 19.0

2" 5.9 11.9 6.9 13.7 7.7 15.3 8.4 16.8 9.1 18.1 9.7 19.4 10.3 20.6 10.8 21.7

Table 1-12 NOTE: This chart was ﬁgured using the maximum run for a single expansion compensator (50 ft.). Refer to

Viega installation manuals for recommended operating temperatures, pressures, tubing fasteners and fastener spacing.

4-6" 4-6"

The fastener shown on the L3 leg may be required to provide additional support depending on how the expansion loop is installed

(horizontal / vertical).

Illustration of Example

L4 = 7.72"

L3 = 3.86"

L4 = 7.72"