Instructions / Assembly
3) Expansion and Contraction
a) PVC will expand and contract with temperature
changes. When running piping to the DiversiTech
concentric vent termination, this physical property of
PVC must be taken into account. General expansion
vs. temperature change based on the length of run
can be found in tables 1 and 2 of this section.
i. Ensure adequate clearance between piping and
other structures. It is recommended that pipe and
ttings are installed at least 1 inch from the
supporting structure. In some instances additional
clearance may be required. Please refer to the
linear expansion tables (Figures 1 & 2) to help
determine if extra clearance is necessary.
ii. Ensure that clamps, hangers and other supports are
intended for use on plastic pipe and allow
necessary pipe movement without damaging the
PVC piping.
Temp. PVC Linear Expansion (ΔL) in inches
Change
Length of Run ()
(°F) 10 20 30 40 50
10 0.04 0.07 0.11 0.14 0.18
20 0.07 0.14 0.22 0.29 0.36
30 0.11 0.22 0.32 0.43 0.54
40 0.14 0.29 0.43 0.58 0.72
50 0.18 0.36 0.54 0.72 0.90
60 0.22 0.43 0.65 0.86 1.08
70 0.25 0.50 0.76 1.01 1.26
80 0.29 0.58 0.86 1.15 1.44
90 0.32 0.65 0.97 1.30 1.62
100 0.36 0.72 1.08 1.44 1.80
Table. 1: Linear Expansion of PVC in inches
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