Fahrenheit Technologies Endurance 50F - Installation; Connecting to Existing Duct Work

10
INSTALLATION
ENDURANCE 50F CONNECTING TO EXISTING DUCT WORK & FURNACES
The 50F is approved to connect to the existing ductwork of a
gas, oil or electric/heat pump furnace with a minimum rating
of 40,000 to 100,000 BTU. The ductwork of the furnaces may
not be hooked in series with each other. This means the warm
supply air of the 50F furnace may not be hooked into the cold
air return of the existing furnace. See example in figure 8. The
cold air return of the 50F furnace is connected to the return air
duct of the existing furnace.
The warm air supply of the 50F furnace connects to the supply
plenum of the existing furnace. Back draft dampers must be
used in the 50F warm air duct and in the warm air plenum of
the existing furnace to prevent the airflow from reversing. The
use of back draft dampers are not required for stand-alone in-
stallations. It is recommended to enter the supply plenum of the
existing furnace above the air conditioning A coil. If the materi-
als used for the warm-air supply duct must have a minimum
temperature rating of 250° F. The plenum of the 50F furnace
must be constructed of metal. This unit is not to be connected
to a chimney flue serving another appliance. Once installed,
check the static pressures in the ductwork to make sure they do
not exceed the limits of the existing central furnace or of the
50F furnace (.45"). Running both furnaces at the same time
should not cause any nuisance tripping of the high limits in
either unit. If being used as central heating, connect to existing
duct work with maximum static pressure of (.48").
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 50F furnace.
Minimum Duct Size
Round:10"
Rectangular:6"x15"
Intake Air Duct should be 10% larger
MaximumStaticPressure:.45"forsupplementaryand
.48" for central hookups.
CAUTION
Do not connect an air conditioner to the furnace.
CAUTION
Do not connect the 50F Furnace to a down flow
furnace system.
Figure 8
Add-On Furnace Stand-Alone Furnace
FAILURE TO FOLLOW INSTALLATION REQUIREMENTS
WILL VOID ALL WARRANTIES.
ConnectingtoExistingDuctWork&Furnaces