MECHANICAL INSTALLATION — MOUNTED RADIATOR COOLING
Factory Mounted RadiatorVentilation
Ventilation of the generator set is necessary to remove the heat and fumes dissipated by the engine, generator, battery, and its accessories as well as provide combustion air.
When the genset has a factory mounted radiator (Figure 25 below), the fan draws air over the set and pushes it through the radiator which has flanges for connecting a duct to the outdoors.
Consider the following when installing a factory mounted radiator genset:
See the genset specification sheet for the design airflow through the radiator, allowable airflow restriction, and minimum air inlet and outlet opening areas. The allowable air flow restriction must not be exceeded. The static pressure (air flow restriction) should be measured to make sure the system is not too restrictive, especially when ventilating air is supplied and discharged through ducts, restrictive grilles, screens, and louvers.
Refer to the ASHRAE (American Society of Heating, Refrigeration and Air Conditioning Engineers) publications for recommendations on duct design if air ducts are required. Note that the inlet duct must handle combustion air flow, ventilating air flow, and must be sized accordingly.
Louvers and screens over air inlet and outlet openings restrict air flow and vary widely in performance. A louver assembly with narrow vanes, for example, tends to be more restrictive than one with wide vanes. The effective open area specified by the louver or screen manufacturer should be used.
The airflow through the radiator is usually sufficient for generator room ventilation.
The radiator fan will cause a slight negative pressure in the room. Therefore it is recommended that combustion equipment such as the building heating boilers not be located in the same room as the genset. If this is unavoidable, it is necessary to determine if there will be detrimental effects, such as backdraft. If so, means such as extra large room inlet openings and/or ducts, pressurized fans, etc. may be required to reduce the negative pressure to acceptable levels.
Other than recirculating radiator discharge air into the generator room in colder climates, all ventilating air must be discharged directly to the outdoors. It must not be used to heat any space other than the generator room.
A flexible duct connecter must be provided at the radiator to take up genset movement, vibration, and transmission of noise.
Ventilating air inlet and discharge openings should be located or shielded to minimize fan noise and the effects of wind on airflow.
Figure 25. Factory Mounted Radiator
PAGE 62 — INDUSTRIAL GENERATOR SETS — APPLICATION & INSTALLATION MANUAL — REV. #4 (09/07/07)