Single Stage Twinning Kit - American Standard *UD Series Operation Manual

Single Stage Twinning Kit

Typical Installations with a Coil
BAYTWIN400A – For use with all 40" furnaces with
White-Rodgers 50A50 integrated furnace controls.
The BAYTWIN400A Twinning Kit is used when
twinning upflow furnaces with identical model
numbers. These identical furnaces must have the
same gas input and airflow.
The return air must be common to both furnaces and
enter through the bottom only. Return air cannot
enter through the back or sides. The reverse flow
switches must be mounted in the blower compart-
ment to prevent furnace operation if one of the
21" WIDTH
21" WIDTH
UPFLOW
UPFLOW
blowers is inoperative. Without a reverse flow switch,
FURNACE
FURNACE
the supply air will recirculate through the furnace with
the inoperative blower and overheat.
The indoor thermostat must energize the "G" circuit
in heating (Electric Heat T-Stat) in order to start both
blowers simultaneously. There will not be a heating
fan on delay period. The 24 volt transformers must be
in phase with each other (10 volts or less between
furnace "R" terminals) and each furnace must be
connected to the same leg or phase of the 115 volt
power source.
A connection between "Y" and "G" on each furnace
low voltage terminal is necessary to operate
both fans at the same speed during heating and cooling.
24 1/2" WIDTH
24 1/2" WIDTH
UPFLOW
UPFLOW
FURNACE
FURNACE
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