HVAC
41
10.2 MAINTENANCE
NOTE
“While starting the Vehicle itself after long dura-
tion (more than 15 days), following procedure
need to be followed to meet AC performance.
Start the vehicle in AC & Blower OFF conditions
in idling for 2-3 minutes, then switch on the AC
and Blower & run it for 2~3 minutes for circula-
tion of refrigerant & oil to lubricate the internal
parts of AC system”.
10.2.1 PRELIMINARY INSPECTION
A. AC SYSTEM PERFORMANCE TEST
1. Place the vehicle in a ventilated, shaded area
free from wind.
2. Check that the surface of the condenser is not
restricted with dirt, leaves, flies, etc. Clean as
necessary.
3. First conduct the open door test followed by
closed door test as mentioned below:
OPEN DOOR TEST
TEST DURATION: 10 min.
INITIAL VEHICLE CONDITIONS
The following conditions to be confirmed before start-
ing the test:
Vehicle stationary with all doors open
Engine Speed
1500 rpm
FOR MANUAL HVAC
Blower Speed
4
th
AC Switch
ON
Temperature Knob
Max. Cool
Vent Knob
Chest
Air Intake
Recirculation air mode
Run the vehicle in the above condition with all doors
open for 10 min. At the end of 10 min insert the
probe at the front vent and record the readings simi-
larly insert the probe at the rear vent and record the
reading.
The reading of front vent should be as per the table
given below:
VENT
AMBIENT TEMPERATURE
< 30ºC
(RH
upto
40%)
30–35ºC
(RH up-
to 40%)
35-
40ºC
(RH
upto
40%)
Above
40º C
(RH
upto
40%)
FRONT
13º C
20º C
24º C
29º C
RH:
Relative Humidity.
NOTE
The above table is applicable if the ambient RH is
40%.
For RH higher than 40% refer the graph below for
acceptable temperatures:
FOR FRONT VENT