Installation Guide
-8-
Duct Work Installation
We strongly recommend that the hot air ductwork be installed by a home heating specialist. If doing the
installation yourself, before you decide which installation will best suit your needs, consult a qualied heating
technician and follow his recommendations as to the safest and most efcient method of installation.
This furnace can be installed in two ways, as a stand alone or parallel unit, with an existing furnace.
SUPPLY AIR (HOT AIR) PLENUM
The warm-air supply duct shall be constructed of metal in accordance with NFPA 90B, 2-1.1. The plenums installed
to the furnace shall be constructed of metal in accordance with NFPA 90B, 2-1.3.
When installing this furnace the hot air plenum is to have a minimum height of 24” (610mm) if the top of the rst
vertical section is not ush with the top of the rst horizontal section of ductwork. If the top of the plenum is ush
with the top of the rst horizontal section of ductwork then the minium height is 15” (381mm).
RETURN AIR (FRESH AIR)
The return (fresh) air intake on the furnace is on the rear of the unit. The ductwork must be mechanically attached
to the unit or UFB908 blower box with sheet metal screws to ensure a proper operation.
STAND ALONE INSTALLATION
If installing this furnace as a stand alone unit, ensure all local codes and all instructions in this manual are followed,
including clearance to combustibles, oor protector specications and safety warnings.
21”
6”
Supply Air (Hot Air) Duct Work Outlet Size
Supply Air Plenum Minimum
Height Of 24”
Supply Air Plenum With
Minimum Height Of 15”