The Heater meets the performance requirements specified when it is mounted in any position from horizontal to vertical
with the ventilation air inlet level with, or higher than the ventilation air outlet. For installation instructions, consult the
Vehicle Technical Manual (see Appendix A) for the appropriate location and mounting methods for the particular vehicle.
DUAL AIR CONVERSION
The Heater can operate in either the dual air, or the single air configuration. The A-20 Heater is supplied in the Dual Air
Configuration, but can be converted to the Single Air Configuration by removing the Combustion Air Adapter as illustrated
in Figure 2-1. Conversion from dual to single air requires the use of a 1/4" socket or nut driver to remove the four (4) hex
head screws, star washers, and flat washers, that attach the Dual Air Adapter to the Heater Ventilation Air inlet.
The letters "DO NOT REMOVE" refer to the center bolt on the Dual Air Adapter
Assembly that holds the inlet swivel to the dual air standoff. Removal of this bolt
may damage the swivel seal assembly.
Figure 2-1. Single Air Configuration