If the servo sticks closed, the system
depends on the electrical anti-ice control to prevent ice
Temperature Control Valve (fig. 1-36).
The system has the temperature control valve located in the bleed air
system between the small outlet on the flow limiting venturi and the
recirculation mixing duct. The temperature control valve inlet duct
connects to the venturi outlet by a sleeve with two band clamps. The
valve inlet port connects to the inlet duct by a threaded coupling
and the outlet port connects to the recirculation mixing duct by a
slide coupling and an "O" ring type seal.
The temperature control
valve and the anti-ice valve have the same features except for the
mounting bracket, electrical connector clocking, and the mounting of
the torque motor.
Operation (fig. 1-37).
The temperature control valve
operates the same as the anti-ice valve. It adds warm air
to the turbine discharge air to maintain the temperature of
the bleed air at the desired temperature.
The valve uses
air from the tapoff prior to the venturi for valve
The torque motor controls the amount of air
allowed to go to the opening of the valve (chamber A), and
the temperature controller controls the torque motor.
Temperature Control Valve.
When the temperature controller sends a signal to the valve
to open, the current in the temperature control