The amount of airflow that reaches the hose is dependent on the efficiency
of the layout of the pipe system. Lines are to be kept as straight as
possible. Tight 90 degree fittings are to be used only at inlet valve
locations and sweep 90's used in all other applications.
1. The Trunk Line
The trunk line connects the furthest inlet valve
to the power unit. Branch lines flowing into the trunk line will connect
all other inlet valves. If the basement/loft is unfinished the trunk line
is best run between the joists in the basement/loft ceiling. The upper
floors can be accessed through built-in cupboards, partition walls and
running adjacent to soil and vent pipes. The location of the trunk line
will greatly depend on the construction of the house and the location
of the power unit.
2. Branch Lines
Branch lines join the remaining inlet valves to
the trunk line. As with the trunk line these lines should be kept as straight
as possible. Forty-five degree fittings should be used to avoid sharp
corners (90 degree fittings) when possible. Airflow direction should always
be considered when installing branch lines.
Avoid Gravity Drops!
A branch line located directly below an overhead
trunk line will accumulate dirt due to the effects of gravity. The result
will be a pile of dirt at the base of the inlet valve every time it is
opened. To avoid this situation the following techniques should be used.