Lotus TURBO ESPRIT Service Manual page 587

Page
72
.
.
SECTION PB
PB
. 6
-
REFRIGERANT QUICK-CHECK PROCEDURE
The following procedure can be used to quickly determine
if
the air conditioning
system has iis required charge of refrigerant. This check facilitates system diagnosis
by pinpointing the problem to the amount of charge i n the system, or by eliminating
this
possibility from the overall diagnosis.
Start engine and 'run' a t
1200
r.p.m. Set controls for
-
maximum cold, with fan at fast speed
Symptom
Continous bubbles
present i n sight glass
No bubbles. Sight
glass clear.
N o appreciable
temperature
differential noted
Temperature
differential noted
at compressor.
Refrigerant i n sight
glass remains clear for
more than
45
secs.,
before foaming and
settling away from
,glass
.
Refrigerant foams and
settles away from sight
glass
in
less than
45
secs.
Cause
System low on
charge.
System
i s
either
fully charged or
empty.
System empty, or
nearly empty.
Even though a
differential i s
noted, there exiis
a possibility of
overcharge. A n
overcharge
fil
led
system w i l l result
i n poor cool
i
ng
.
System over-
charged.
Remedy
Check with leak detector.
Correct leak,
i f
any, and
f i l l
system to correct charge.
Feel high and low pressure pipes
of compressor. High pressure
pipe should be warm, low
pressure pipe should be cold.
Switch 'off' engine. Re-charge
system with refrigerant, and
check with leak detector.
Check by disconnecting the
compressor clutch connection
(at upper front) while observing
the sight glass.
Verify with performance checks.
System correctly
Continue checking out system
using checks as previously given.