Generac Power Systems 00862-1 - Manual (Page 22)

COOLING AND VENTILATING AIR
It is absolutely essential that an adequate flow of air for
cooling, ventilating and engine combustion be supplied
to the generator set. Without sufficient air flow, the
engine-generator quickly overheats. Such overheating
can cause serious operating difficulties and may also
cause fire and personal injury. The installer must make
sure that sufficient air is available to the generator for
cooling, ventilating and combustion. The installer must
also provide for a path for exhausting the cooling air to
the exterior of a compartment, if so equipped.
DANGER; Never use discharged cooling air for heat­
ing or permit such air to enter the vehicle interior.
This air contains deadly carbon monoxide gas and
other poisonous, flammable or explosive gases.
GENERATOR AIR FLOW
Engine operation drives cooling fans for the 2-stage
cooling air system. A pressure fan draws cooling air
into the top of generator (Figure 22). This air flow
cools'the engine-generator and electronic compo­
nents. The second part of the cooling system, a suc­
tion fan, draws air that is heated from a hot engine
into a collector pan at the base of the unit. This heat­
ed air (although cooler than exhaust muffler) is direct­
ed across the muffler to cool it. The heated air flow is
then deflected out the bottom toward the ground.
Figure 22 — Air Flow Through Engine-Generator
COOLING AIR INLET OPENINGS
The air inlet opening is illustrated in the compartment
floor cutout in Figure 21. If the vehicle will be parked
on a concrete surface for an extended period of time
with the generator running, an additional air inlet may
be provided in the compartment door as shown in
Figure 23.
NOTE: Screening, louvers, or expanded metal that
cover air openings restrict air flow that you must com­
pensate for by making the actual air opening propor­
tionately larger. See “Compensating for Restrictions.”
Figure 23 — Air Inlet in Compartment Door
75 SQUARE INCHES
UNRESTRICTED
MINIMUM OPENING
IMPORTANT: BE SURE TO MEET THE MINIMUM
CLEARANCES ILLUSTRATED IN FIGURE 18.
When the unit is installed on a suspended mounting
system, one of several different methods of supplying
air flow may be used as follows:
• Provide a door in the vehicle skirt having an air inlet
opening (Figure 24).
Figure 24 — Suspended Mount: Inlet Door
Using ductwork (Figure 25). The installer must be sure air
is available to the back of the generator since air inlets
are located at the back.
By providing an opening in the vehicle skirt and space
behind the generator for cooling air flow (Figure 26).
Recommended clearance behind the back of the genera­
tor is at least 3 inches.
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