S&P JENcoFAN EO, Installation, Operation And Maintenance Manual

6

FIELD INSTALLED DUCT COLLARS

Ductwork Installation

All ductwork should be installed in accordance with local codes. The installing contractor is 
responsible for adherence to codes and restrictions. Generally, the duct system will perform best 
and will ensure easy installation if installed in the most direct and simple manner.

NFPA-96 requires that the exhaust duct must be installed using 16-gauge carbon steel or 
18-gauge stainless steel with all joints and seams welded liquid tight. Listed factory-built grease 
duct is an exception when installed according to manufactures instructions. NFPA-96 further 
requires that a minimum of 500 FPM (Feet Per Minute) velocity must be maintained in the exhaust 
duct. There is not a specified maximum however, exhaust velocity should not exceed 2200 FPM. 
Install access panels where required. In any event, conformance to local codes must be adhered 
to, unless variance is obtained.

Make-up air ductwork should contain adequate filtering provisions somewhere in the system 
before it is introduced into kitchen space, or in the hood. Select hood models require a make-up 
air fire damper with fusible link installed at the collar. Access to the fusible link must be installed in 
supply duct. Only use rigid type duct for make-up air. Do not use “flex” duct. This duct should be 
in accordance with project specifications and installed in accordance with standard SMACNA 
Low Pressure requirements.

Field Installed Duct Collars

When ordered, exhaust and supply collars are shipped loose (not connected to hood) and 
intended to be field installed on some projects. Determine the location of exhaust/supply collar(s). 
Collars should be located as close to center (left to right with a max. offset of one fourth the 
total length) of hood as possible. When two exhaust and/or supply collars are required, equal 
distance between collars (left to right) should be maintained. Loose collars are tack welded to top 
of hood (back of crate). Break tack welds to remove collars.  Exhaust collars must be folded up 
before installing. Fire Dampers are shipped loose inside the crate.

Exhaust Collars

For collar to duct connection see “Exhaust Duct Systems” Chapter 7 of NFPA-96. 
For field installed duct collars see above.

Supply Collars

Install make-up air duct per local standard. For field installed duct collars, see above.

Important:

 Refer to your AHJ (Authority Having Jurisdiction) for requirements and/or questions 

on local codes.

Clearance to Combustible Materials

A further note on ductwork is important. Please consult NFPA-96 4.2 Clearance. An 18 in. 
clearance is required for unprotected combustible material. This clearance may be reduced if 
the combustible material is protected by an engineered construction system acceptable to the 
authority having jurisdiction, or by the use of materials or products listed for protection purposes 
Consult NFPA-96 and local codes before installing any hood system or exhaust ductwork.