Connecting To Existing Duct Work - St. Croix SCF-Revolution Installation & Operation Manual

Connecting To Existing Duct Work & Furnaces
Figure 8
The SCF-Revolution may be connected to the existing ductwork of a Gas, Oil or Electric/Heat Pump
furnace with a minimum rating of 45.000 BTU. The ductwork of the furnaces may not be hooked in
series with each other. This means the Warm Supply Air of the SCF-Revolution may not be hooked
the Cold Air Return of the existing furnace. See example in figure 8 above. The Cold Air return of the
SCF-Revolution is connected to the Return Air Duct of the existing furnace. The Warm Air Supply of
the SCF-Revolution connects to the Supply Plenum of the existing furnace. Back Draft Dampers
must be used in the SCF-Revolution Warm Air duct and in the Warm Air Plenum of the existing
furnace to prevent the airflow from reversing. It is recommended to enter the Supply plenum of the
existing furnace above the Air Conditioning A coil. The materials used for the Warm-Air supply duct
must have a minimum temperature rating of 250 degrees F. The Plenum of the SCF-Revolution must
be constructed of metal. Once installed as an Add On furnace check the Static pressures in the
ductwork to make sure they do not exceed the limits on the existing Central furnace or of the SCF-
Revolution. Running both furnaces at the same time should not cause any nuisance tripping of the
High Limits in either unit.
Follow all instructions when connecting to existing ductwork. Connecting the Warm Air Supply
to the Cold Air return may cause harm to the existing furnace and may void the warranty of
both the existing furnace and the SCF-Revolution.
It is not recommended to hook an Air Conditioning unit to this system.
SCF-Revolution Manual
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