The present invention concerns a method for cooling a passenger compartment in
a hybrid vehicle that operates an engine intermittently during vehicle operation,
the hybrid vehicle having an HVAC system including an HVAC duct, a blower adapted
to direct a flow of air through the HVAC duct, and an evaporator located within
the HVAC duct. The method includes the steps of operating the blower; operating
the compressor; allowing a predetermined amount of ice to form on the evaporator
during operation of the compressor; turning off the vehicle engine; ceasing operation
of the compressor; measuring an indicator corresponding to a remaining amount of
the predetermined amount of ice formed on the evaporator; and re-starting the compressor
when a predetermined air temp in air duct is reached.