MAHLE RTI TC640 - Manual (Page 15)

RTI Technologies, Inc.
September 15, 1997 Page 14
PROBLEMS & SOLUTIONS
On rare occasion the TC640 may seem to be performing differently or not at
all. Experience has shown that varying operating conditions can affect the
performance characteristics of the TC640. The temperature of the vehicle A/C
System will affect how the TC640 performs.
Following are typical problems with explanations of the possible cause and
solution.
PROBLEM: My TC640 worked fine all last Summer. I got it out today for the
first service job this Spring and it is very slow in evacuating the
system.
SOLUTION: Today's Spring temperature may be much lower than the average
temperatures during the summer months. Maybe the vehicle was
brought in from outside where the temperature is very low.
The refrigerant in the vehicle will not be under as high a
pressure at lower temperatures and the TC640 will take longer
to draw a vacuum. More cycles may be required to completely
recover the refrigerant.
PROBLEM: I put 2.5Kg of refrigerant into the TC640 using the Recycle Mode.
When I checked the sight glass on the Charging Cylinder, there
was less than 2.5Kg. I lost Refrigerant. The unit must leak.
SOLUTION: Due to temperature changes, some refrigerant may condense into
liquid form and stay in tubes and other components in the circuit
preceding the Charging Cylinder. This is normal and will explain
why all refrigerant is not visible in the sight glass.
PROBLEM: I can not get the TC640 to draw a vacuum as indicated on the Low
Side Gauge.
SOLUTION: Check Hoses for restrictions.
PROBLEM: When I try to fill the Charging Cylinder from an auxiliary
cylinder of clean refrigerant, the TC640 is really slow or shuts
down.
SOLUTION: The auxiliary cylinder will cool due to the vaporization of
refrigerant. This causes the pressure to decrease.
Use a heat belt to increase the speed of recycling by the TC640.