Component Maintenance Manual
EFFECTIVITY: ALL
21-00-22
Introduction
Page
15
JULY 21, 2011
2.3.5.2
BLOWER MOTOR: The blower motor (1250210-1) operates on 24 VDC with a
current draw of 5 amps and has a design RPM of 5225. The blower motor is a four
brush design with an integrated controller and was selected for its efficiency, excellent
controllability, long life and low vibration at high speeds. The motor has two speeds,
low speed designed for the heating recirculation requirement and high speed
designed for maximum system cooling.
2.3.5.3
BLOWER WHEEL: The blower wheel is the component that is used in concert with
the blower motor and provides for the movement of air. It is made of light weight
aluminum that provides superior strength and durability.
2.3.5.4
BLOWER SCROLL: The blower scroll is constructed of high impact, fire retardant,
self extinguishing, and corrosion resistant, lightweight polycarbonate material . It is
nickel plated to give it superior strength and durability qualities. The blower scroll has
successfully passed blower wheel containment testing.
2.3.5.5
EXPANSION VALVE: The expansion valve is an automatic thermostatic type. The
valve provides the proper refrigerant flow while maintaining constant return gas
superheat at all evaporator heat load conditions. Controlling the evaporator
refrigerant flow based on cooling demand prevents coil freeze up. This allows the
system cooling capacity to best meet transient aircraft heat load demands.
2.3.5.6
EVAPORATOR HOUSING: The evaporator housing is constructed of high impact, fire
retardant, self extinguishing, and corrosion resistant, lightweight polycarbonate
material.
