Run the low-voltage wiring along the trunk line; at
approximately 12”-18” (305 mm - 457 mm) intervals, use
electrical tape to secure the wire to the tubing. Then, run
wiring along the branch lines from the inlet lines to the trunk
line. Also secure this wiring with electrical tape.
At the joint of the inlet line and the branch line, make a
two-wire connection. Use wire nuts to make the connections
and insulate each connection with electrical tape.
At the junction of every branch line and the trunk line, cut the
trunk line wire and connect it to the branch line wire. Connect
this wiring in groups of threes–one branch wire, one in-coming
trunk line wire, and one out-going trunk line wire. Insulate all
wire connections with electrical tape.
Complete all wiring connections up to the power unit’s intake
access hole. You will make this connection when you mount
and connect the power unit. If, for some reason, you want to
connect the wire as you go along, make the same two-wire
and three-wire connections where required.
Assembling a Basement Trunk Line
Basically, the tubing
network is assembled the
same way for a basement
installation. Begin the
trunk line at the farthest
inlet line from the power
unit. Measure and cut the
inlet tubing to the length
required to align the trunk
line with the joists or
ceiling. Cement the inlet
tubing and connect at 90°
elbow. Then, run the trunk
line until you reach a
branch line junction point.
Attach the tubing to the
joists or ceiling with either
perforated metal or support
strapping. Make all branch
line connections in the
same way you would an
attic installation. Make sure
that all branch lines enter
the trunk line at an angle
that is at least level with the
trunk line. Make sure all the
fittings are oriented so the
air flows toward the power
unit. Complete the trunk line
to the power unit location.
Using Flexible Tubing
Flexible tubing may be used to circumvent an obstacle or to
make a difficult turn. In the example illustrated here, the
flexible tubing is used in order to run a branch line under a
support beam. Attach this tubing to the PVC tubing, cementing
only the outside of the PVC tubing as you would for a
hard-fitting connection. Whenever you use the flexible tubing,
you must secure both ends of it with support strapping.
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