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I − UNIT COMPONENTS
A − Blower Contactor K3
B − Economizer Relay K43
Relay K43 is a single−pole double throw relay used to con-
trol the economizer. When there is a call for cooling, K43−1
contacts close energizing the economizer and blower con-
tactor K3. See wiring diagram.
C − Blower Motor B3
See Page 12 for blower drive specifications and blower motor
electrical data.
D − Blower Motor Overload Relay S42
Relay S42 is used for M voltage and units with high effi-
ciency motors only. S42 is connected in line with the blower
motor to monitor the current flow to the motor. When the
relay senses an overload condition, a set of N.C. contacts
open to de−energize all 24 volt circuits.
E − Terminal Block TB1
All field wring connections are made at terminal block TB1.
F − Condensate Pan and Over Flow Relay K220 &
Switch S149
A reversible drain pan is provided. Never connect conden-
sate drain to a closed system. Condensate drain line must
have a trap in the line at the unit exit. K220 and S149 are
field installed and used to prevent condensate overflow. In
the event of a blocked drain plug and condensate begins
rise, N.O. S149 will close energizing relay K220. N.C. K220
opens de−energizing the the TAA unit.
FIGURE 1
Coil
Expansion Valve
Blower
Control Box
TAA072/090/120/150
Coil
Expansion Valve
Blower
Control Box
TAA180/240
Y, G, AND J VOLTAGE
WIRING
M VOLTAGE OVERLOAD
WIRING
THREE−PHASE THERMAL
OVERLOAD RELAY (S42)
CONTACTOR
(K3−1)
GROUND
LUG
TERMINAL
STRIP (TB1)
BLOWER
RELAY (K43)
CONTROL PANEL
FIGURE 2
