Generac Power Systems 0940-1 - Manual (Page 24)

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
heating or permit such air to enter the vehicle interi­
or. 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 and into the side of the control
panel (Figure 22). This air flow cools the engine-gener­
ator and electronic components. The second part of
cooling system, a suction fan, draws air that is heated
from a hot engine into a collector pan at the base of
the unit. This heated air (although cooler than exhaust
muffler) is directed 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
Ideally, you should provide three air inlet openings,
whether the generator is housed in a conventional
compartment or not. Two of the openings should be 10
square inches and located as shown in Figure 23. The
third opening should provide for a minimum of 40
square inches unrestricted and be located lower on the
compartment door.
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.”
For conventional compartment mounted units, the air
inlet is generally provided in the compartment door.
Figure 23 — Air Inlet in Compartment Door
10 SQUARE INCHES
(OPTIONAL OPENINGS)
40 SQUARE
INCHES
(MINIMUM
OPENING)
IMPORTANT; IF YOU PLAN TO INSTALL THE GEN­
ERATOR
IN A COMPARTMENT, BE SURE TO
LEAVE AT LEAST ONE INCH (2” RECOMMENDED)
OF CLEARANCE BETWEEN THE GENERATOR AND
COMPARTMENT
WALLS AND CEILING. INCLUDE
26 GAUGE GALVANIZED STEEL LINING AND
SOUND INSULATION WHEN YOU MEASURE FOR
THIS 1 INCH (2” RECOMMENDED) CLEARANCE.
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 open­
ing (Figure 24).
Figure 24 — Suspended Mount Inlet Door
be sure air is available to the top of the generator since air
inlets are located at the top.
By providing an opening in the vehicle skirt and space
above the generator for cooling air flow (Figure 26 on Page
23). Recommended clearance above the top of the gener­
ator is at least 2 inches.
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