Generac Power Systems 0661-5 - Manual (Page 22)

Using ductwork (Figure 23). The installer must be sure air
is available to the top of the generator since air inlets are
located at the top.
Figure 23 — Air Inlet Using Ductwork
above the generator for cooling air flow (Figure 24).
Recommended clearance above the top of the generator
is at least 2 inches.
Figure 24 — Air Inlet in Vehicle Skirt
COMPENSATING FOR
RESTRiaiONS
Such materials as screening, louvers, or expanded
metal can restrict the free flow of air. Compensate for
this restriction by making the actual air opening pro­
portionately larger.
Some materials may offer only a 60 percent “free air
inlet area." Other more efficient materials may provide
up to a 90 percent free air inlet area. The percentage
of free air inlet opening is usually available from the
material supplier or manufacturer.
TO DETERMINE THE ACTUAL AIR INLET OPEN­
ING SIZE REQUIRED, DIVIDE 40 SQUARE INCHES
BY THE PERCENTAGE OF FREE AIR INLET AREA
FOR THE MATERIAL YOU WILL USE.
For example: If you plan to use screening with an
80% free air inlet area, divide 40 by 0.8, which results
in 50 square inches. Minimum actual size of air inlet
opening in this case is 50 square inches. An opening
that measures 4 inches wide by 12-1/2 inches long
provides the required air flow (4 x 12.5 = 50 square
inches).
TESTING THE INSTALLATION
Generac recommends testing the installation to be
sure adequate cooling air flow is available to the unit
before placing the unit into service. If the unit shows
signs of overheating, you will need to enlarge the air
openings. Never place a unit into service until
absolutely certain that cooling and ventilation is ade­
quate.
IMPORTANT: YOU MUST TEST THE INSTALLA­
TION ESPECIALLY IF YOU BRING IN AIR FROM
BELOW THE GENERATOR SET.
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