Chapter 2
DESCRIPTION OF OPERATION
DESCRIPTION
2.0
General
A. The cabin heater is designed to provide fresh, conditioned (heated) air from outside the aircraft
to warm the crew and passenger areas during any phase of flight. In addition, the heater is
designed to maintain a desired cabin temperature within the limitations of the given heater. A
typical I-Series heater is shown in cutaway in Figure 2.1.
B. Each heater system consists of a heater assembly, a ventilating air blower, a combustion air
blower, nozzle holder, solenoid valve assembly, single piece spark plug, high voltage ignition
system, combustion air pressure switch, overheat switch, cycling switch, and necessary radio
noise suppressors. Optional equipment includes a duct switch, fuel pump, fuel regulator and
shutoff valve, combustion air blower inlet adapter and a fanning strip (electrical connectors).
All components except the combustion air blower, duct switch, fuel regulator and shutoff valve
and fuel pump are combined into one assembly to facilitate installation and service operations.
The optional equipment items are provided as separate components since they may be
mounted at different locations in the aircraft. The basic heater assembly consists of the
exhaust outlet, jacket, combustion head, and combustion tube. The combustion tube is made
of Inconel® alloy steel with most other parts made of stainless steel alloy.
99M90
21-40-01
Page: 2-1
Rev. New
Issued: May 9, 2012
I-Series Combustion Heater
Owners Manual
Fig. 2.1
Cutaway of Typical
I-Series Heater