Installation Guidelines For Stationary Air-Cooled Generators; Annex A - Explanatory Material - Generac Power Systems PowerPact 7.5 kW Installation Manuallines

Site Selection and Preparation
Install the generator set, in its protective enclosure,
outdoors where adequate cooling and ventilating air is
always available (Figure
• The installation of the generator must comply
strictly with ICC IFGC, NFPA 37, NFPA 54, NFPA
58, and NFPA 70 standards.
•
Install the unit where air inlet and outlet openings
will not become obstructed by leaves, grass, snow,
etc. If prevailing winds will cause blowing or
drifting, consider using a windbreak to protect the
unit.
• Install the generator on high ground where water
levels will not rise and endanger it. This unit should
not operate in or be subjected to standing water.
• Allow sufficient room on all sides of the generator
for maintenance and servicing. This unit must be
installed in accordance with any local, state, or
national codes for minimum distances from other
structures.
• Clearance from the ends and front of the generator
must be 3 ft (0.91 m). This includes shrubs,
bushes, and trees. Clearance from the back of the
generator must be a minimum of 18 in (457 mm).
Clearance at the top should be a minimum of 5 ft
(1.52 m) from any structure, overhang, or
projections from the wall.
IMPORTANT NOTE: Mechanical and gravity
outdoor air intake openings for HVAC supply air
systems shall be located not less than 10 feet
(3048mm) horizontally
enclosure. See Section 401 in the ICC
Code for any additional requirements.
• DO NOT install under wooden decks or structures
unless there is at least 5 ft (1.52 m) of clearance
above the generator.
• Install the unit where rain gutter down spouts, roof
run-off, landscape irrigation, water sprinklers, or
sump pump discharge does not flood the unit or
spray the enclosure, including any air inlet or outlet
openings.
• Install the unit where services will not be affected
or obstructed, including concealed, underground,
or covered services such as electrical, fuel, phone,
air conditioning, or irrigation. This could affect
warranty coverage.
•
Where strong prevailing winds blow from one
direction, face the generator air inlet openings to
the prevailing winds.
•
Install the generator as close as possible to the fuel
supply to reduce the length of piping. REMEMBER:
LAWS OR CODES
DISTANCE AND LOCATION. In the absence of
local codes regarding placement or clearance, we
recommend following these guidelines:
12
3-1). Consider these factors:
from the generator
Mechanical
MAY REGULATE THE
– Install the generator as close as possible to the
transfer switch. REMEMBER: LAWS OR CODES
MAY REGULATE THE DISTANCE AND
LOCATION.
– The generator must be installed on a level
surface. The generator must be level within 0.5
in (13 mm) all around.
– The generator is typically placed on pea gravel,
compacted soil, crushed stone, or a concrete
pad. Check local codes to see what type is
required. If a concrete pad is required, all
applicable codes should be followed.
Installation Guidelines for Stationary Air-Cooled
Generators
NFPA 37 is the The
Association's standard for the installation and use of
stationary combustion engines. Its requirements limit the
spacing of an enclosed generator set from a structure or
wall (Figure 3-1).
NFPA 37, Section 4.1.4, Engines Located Outdoors:
4.1.4.1 Engines and, if provided, their weatherproof
housings installed outdoors shall be located at least 5 ft
(1.52 m) from openings in walls and at least 5 ft (1.52 m)
from structures having combustible walls except as
provided in 4.1.4.1.1 or 4.1.4.1.2.
4.1.4.1.1 A clearance less than 5 ft (1.52 m) shall be
permitted where all portions of structures closer than 5 ft
(1.52 m) from the engine enclosure have a fire resistance
rating of at least one hour.
4.1.4.1.2* A clearance less than 5 ft (1.52 m) shall be
permitted where it has been demonstrated through
methods acceptable to the authority having jurisdiction
that a fire within the enclosure will not ignite combustible
structures.
Annex A — Explanatory Material
A4.1.4.1.2 Means of demonstrating compliance are by
means of full scale fire test or by calculation procedures.
Because of the limited spaces frequently available for
installation, it has become apparent that exception (2)
would be beneficial for many residential and commercial
installations. With that in mind, the manufacturer
contracted with an independent testing laboratory to run
full scale fire tests to assure that the enclosure will not
ignite combustible materials outside the enclosure.
NOTE: Southwest Research Institute testing approves
18 in (457 mm) installation minimum from structure
(Figure 3-1, C). Southwest Research Institute is a
nationally recognized third party testing and listing
agency.
The criteria was to determine the worst case fire scenario
within the generator and to determine the ignitability of
items outside the engine enclosure at various distances.
The enclosure is constructed of non-combustible
Installation Guidelines for 60 Hz PowerPact™
National Fire Protection