Figure 5-3.--Anti-icing modulating valve.
Thermostats
through the modulator valve to the ejector manifold,
out the jet nozzles, and into the wing leading edge
The wing leading edge pneumatic thermostat is
plenum area. The bleed air is then directed across a
installed adjacent to each modulating valve (fig. 5-2).
pneumatic thermostat. Increased temperature across
The thermostat controls air pressure on the modulating
the thermostat actuates the sensor and opens a bleed
valve diaphragm, and thereby controls the valve opening.
passage from the diaphragm chamber. This reduces the
The unit is composed of a probe and a valve
pressure on the diaphragm and allows a spring to close
assembly (fig. 5-4). The probe is a core made of layers
the main valve.
Figure 5-4.--Wing leading edge thermostat.
5-5
