COOK GR User Manual

1

GI/GR

Gravity V ents

®

Installation, Operation, And Maintenance Manual

This publication contains the installation instructions for

standard units of the GI/GR Gravity Ventilators.

Carefully read this publication and any
supplemental documents prior to any installation
or maintenance procedure.

Loren Cook Company Gravity Ventilation catalog

provides additional information describing the equipment,

unit performance, available accessories, and specication

data.

For additional safety information, refer to AMCA
publication 410-96, Safety Practices for Users and
Installers of Industrial and Commercial Fans.

All of the publications listed above can be obtained
from Loren Cook Company by phoning [phone],
extension 166; by FAX at [phone]; or by e-mail at
[e-mail].

For information and instructions on special equipment,
contact Loren Cook Company at [phone].

Receiving and Inspection

Immediately upon receipt of a GI/GR unit, carefully
inspect it for damage and shortage.

• Check dampers (if supplied) for free operation of
moving parts.

• Record on the Delivery Receipt any visible sign of
damage.

Handling

Lift the unit by the lifting lugs or shipping carton (Refer to
Figure 4). NOTICE! Never lift by the hood or end panels.

Storage

If the unit is stored for any length of time prior to
installation, store it in its original shipping crate and protect
it from dust, debris and the weather.

Installation

Knockdown Reassembly (Refer to gure 3)

All knocked down hoods are factory preassembled and
then knocked down for shipping. Reassemble by aligning
holes and bolting together.

Attach hood sections together by overlapping joining
seams. Align holes and use the provided section rail splice
and bolts to secure hood section together.

Code requirements and environmental effects

The attachment of roof mounted fans to the roof
curb as well as the attachment of roof curbs to
the building structure must exceed the structural
requirements based on the environmental loading
derived from the applicable building code for the

site. The local code ofcial may require variations

from the recognized code based on local data.
The licensed engineer of record will be responsible
for prescribing the correct attachment based on
construction materials, code requirements and

environmental effects specic to the installation.

Failure to follow these instructions could result in
death or serious injury.

2

For units with birdscreen: fasten securely to the
section rail inside of the hood with speed screws(A)
and washers(B) stretching the birdscreen(C) tight as
possible. For aluminum birdscreen replace washer with

(provided) aluminum strips. On ltered units, the (optional)

birdscreen comes attached to the top of the throat.

Figure 1

C

B

A

For units with two piece mounting channel: insert
mounting channel splice into the two pieces of mounting
channel aligning the holes. Fasten securely to base with
bolts and nuts (provided).

For units with multiple base assemblies: fasten securely
the base sections through the base splice bracket using
bolts and nuts (provided).

1. Set assembled hood on base, aligning the mounting
bracket and section rail holes.

2. If necessary, attach base to mouting angle with bolt
(provided) through base into the nut on the support
angle (provided)

Hood panel

Throat

Maintenance

Hood Access

To access the throat of the unit, take the entire hood off
by removing the bolts attaching the mounting bracket to
the mounting channels. GR units with less than a 73” throat
length and GI units with less than a 61” throat length can
be hinged. Hinging is accomplished by removing the bolts

on one side and loosening the two bolts (Refer to gure 2)

on the other side. Care should be taken when hinging the
hood, especially in high wind conditions.

Figure 2

Filters

Filter inspection and cleaning intervals can vary from

once a week to twice per year depending on contaminant

present and acceptable pressure drops across the lter.
Under most conditions lters may be cleaned with hot water

and a mild soap solution (such as dish washing liquid) or

steam. Some caustic cleaners will damage the lter. If in

doubt, please consult the factory for a compatibility list.
High pressure spray washers should be limited to 2,000
PSI operating pressure. Every attempt should be made to

remove the contaminants from the lter in a “backwash”
ow (note airow arrow on the lter frame). Once the lter
is dry, it may be returned to the appropriate lter racks
in the same orientation (airow direction) as they were

removed.

Warranty

Loren Cook Company warrants that your Loren Cook
fan was manufactured free of defects in materials and
workmanship, to the extent stated herein. For a period of
one (1) year after date of shipment, we will replace any
parts found to be defective without charge, except for
shipping costs which will be paid by you.

This warranty is granted only to the original purchaser
placing the fan in service.

This warranty is void if the fan or any part thereof has

been altered or modied from its original design or has

been abused, misused, damaged or is in worn condition or
if the fan has been used other than for the uses described
in the company manual. This warranty does not cover
defects resulting from normal wear and tear.

To make a warranty claim, notify Loren Cook Company,

General Ofces, 2015 East Dale Street, Springeld,
Missouri 65803-4637, explaining in writing, in detail,
your complaint and referring to the specic model and

serial numbers of your fan. Upon receipt by Loren Cook

Company of your written complaint, you will be notied,

within thirty (30) days of our receipt of your complaint,
in writing, as to the manner in which your claim will be
handled. If you are entitled to warranty relief, a warranty
adjustment will be completed within sixty (60) business
days of the receipt of your written complaint by Loren Cook
Company.

This warranty gives only the original purchaser placing

the fan in service specically the right. You may have other

legal rights which vary from state to state.

For fans provided with motors, the motor manufacturer
warrants motors for a designated period stated in the
manufacturer’s warranty. Warranty periods vary from
manufacturer to manufacturer. Should motors furnished
by Loren Cook Company prove defective during the
designated period, they should be returned to the nearest
authorized motor service station. Loren Cook Company will
not be responsible for any removal or installation costs.