United States Stove Company NITED STATES STOV 1602M - Manual (Page 5)

5 USSC
INSTALLATION #3
The baffle on this system should be made the full width of
the furnace plenum in order to properly direct the air into
the distribution ducts.
INSTALLATION #2
Extending the hot air duct from the furnace into the existing
plenum will help direct the flow of air from the furnace as
well as the flow in the existing furnace. Ducting entering
the existing plenum at an angle (approximately 45 degrees)
will facilitate air flow from the furnace while diverting air
from the existing furnace.
THE PLENUM OPENINGS DIFFER
BETWEEN THE 1602 AND 1802
MODEL 1602 - 13” x 18” Rectangular
MODEL 1802 - 18” x 18” Rectangular
RETURN AIR IS VERY IMPORTANT
When installing a Clayton Furnace, return air MUST BE in-
corporated into the system. Return air can be provided
by installing a separate duct system or by tying into the
cold air return of an existing gas or oil furnace. The cold
air return duct can be connected to the furnace with ei-
ther a factory manufactured U. S. Stove filter box, model
UFB908 or an equivalent fabricated from sheet metal.
When installing a cold air return, the minimum size shall
be a 16” x 20” or equivalent (320 sq. in.) in order to insure
proper furnace performance. Failure to provide return air
ducts of the specified size will void your warranty.
A filter should be installed in the cold air return. Furnace fil-
ters should be checked and cleaned/replaced regularly.
If return air is not provided, the warm air distributed into
your home will be restricted and the efficiency of the
furnace is decreased. Without a return air system, warm
air will be drawn into your basement, unnecessarily heat-
ing unused areas of the home. In extreme cases, if your
basement or utility room is fairly airtight, the blowers on
the furnace could depressurize the room and pull toxic
flue gases from the furnace, a gas water heater, or gas
furnace. The fumes could then be distributed throughout
the house.
COMBUSTION AIR
All fires need air (specifically oxygen) to burn. Furnaces,
fireplaces, and wood burning furnaces need enough oxy-
gen for complete combustion of their fuels. The incom-
plete combustion that takes place when a furnace is “air
starved” causes carbon monoxide (CO) to be formed
in quantities that can be dangerous inside a well sealed
house. Having a source of combustion air from outside
the home will prevent “air starvation” of the furnace. A
simple positive air supply can be constructed using dryer
vent and a modified termination.
NEGATIVE
PRESSURE IN
BASEMENT
PLENUM OPENING