Datasheet

Optimal Vent Positioning
Protective Vents
adhesive vents
Choosing the Optimal Position for Your Vent
Figure 1: The position of the vent directly affects the amount of condensation.
Both top boxes are not vented
Bottom left box is
vented at the left
and right side
Bottom right box is
vented at the right
side only
Positioning Options for Gore PolyVents
Selecting the best Position for your Vent
Depends on its Primary Purpose:
• Equalizing pressure:
To equalize pressure, it is best to position the vent in the area
most protected from exposure to the outside environment.
• Reducing condensation:
To reduce condensation, it is usually best to position the vent
near the top of a vertical wall of the housing so that the warm,
humid air can easily escape as it rises. However, you should
also take into account the location of components and areas
that moisture will most likely damage, such as the lens of a
street light or a printed circuit board. In this case, it is more
important to place the vent near the critical area than near
the top of the housing to eliminate potential condensation.
drop edge
drop edge
Position on
Enclosure
Advantages Disadvantages
Top
• Rapid temperature changes create significant pressure differentials during
heavy rain. The water can block the vent and reduce its ability to equalize
pressure.
Vertical wall
• The open design of the vent body and cap and the
membrane’s dome shape enable water to wash
particulates off the membrane.
• Temperatures and humidity are usually higher at the top
of an enclosure; therefore, a position on the vertical wall
close to the top is the best position for venting.
Bottom
• Often the preferred location because of existing power
supply openings, this position prevents rain from falling
directly on the vent.
• Cables can protect the vent from mechanical damage.
• Integrating a drop edge into the enclosure keeps water
away from the vent (Figure 2).
• Heavy rain can collect in the vent cap and remain until it evaporates.
• After liquid has evaporated, the residual dirt and dust provide an environment
for plants, fungus, etc., to grow.
Figure 2: A drop edge on the enclosure blocks water from the vent.