Kohler Generator Sets 20--2800 kW - Manual (Page 23)

TP-5700 7/93 11 Section 4 Air Requirements
Section 4 Air Requirements
4.1 General
An ample flow of clean, cool air is required to support
combustion and dissipate heat. Approximately 70% of
the heat value of fuel consumed by an engine will be
rejected to the cooling system and exhaust.
Battery compartment ventilation. To prevent the
accumulation of explosive gases, ventilate
compartments containing batteries.
If a generator set is to be located in a building or enclosure,
make certain that adequate air intake and air outlet
openings are provided. If air flow provided by the
engine-generator cooling fan is not sufficient to prevent
excessive temperatures, other means such as ductwork
and/or ventilating fans will have to be used to provide
adequate air flow. If an exhaust fan is used, (Figure 4-1
and Figure 4-2) check the fan’s capacity in cubic feet
(cubic meters) per minute. Follow the fan manufacturer’s
recommendations to determine the size of the inlet and
outlet openings.
In certain cold climate applications, controlled
recirculation may be used as a means of heat recovery;
however, special equipment such as thermostatically
activated louvers and fans are needed to prevent engine
and
engine room overheating. The uncontrolled
recirculation of heated air within an enclosure must be
prevented. Otherwise, the temperature in the enclosure
quickly rises to a point where efficient cooling is no longer
possible. With a properly designed ventilation system, a
sufficient
temperature differential is not hard to
maintain—even on the hottest days. Make certain air
inlets and outlets cannot be blocked by snow. Air inlets
and outlets should also be kept clean and unobstructed
at all times. The direction of the prevailing wind should be
considered when positioning outlets. If wind velocity is
considerable, it tends to cancel the effects of the engine
or exhaust fan. When strong prevailing winds are
anticipated, face the air inlet into the wind and the outlet in
the opposite direction. See Section 4.6, Liquid-Cooled
Models, for additional suggestions.
Figure 4-1 Exhaust Fan-Operated Louvers (fan not
shown)
Figure 4-2 Fans Required On Some Installations