Figure 71.8. Battery compartment shut-of valve.
personnel heater. An electrically operated fan causes
153. Battery Compartment Shut-off Valve
air to flow through the core, where heat is transferred
from the heated liquid, and circulated throughout the
cab. A separate blower diverts warm air from the heater
core, through apertures in the instrument panel, to the
A 4-way valve (fig. 71.8) allows the heated fluid to
windshield to eliminate and prevent frost and fogging
by-pass the battery compartment to prevent overheating
conditions on the glass.
the storage batteries.
155. Personnel heater
When the exterior temperature is not sufficiently
cold to warrant use of the liquid heater, the personnel
heater may be used by actuating the circulating pump in
The personnel heater (fig. 71.9) utilizes liquid which
the liquid heating system, utilizing liquid which has been
has been heated by the liquid heater on the engine, to
heated by the truck engine to supply the heater core.
provide warm air to the cab of the truck. The heated
fluid circulates through a honeycomb core in the