CPS TEMP-SEEKER TM360C Owner's Manual - Page 11

Browse online or download pdf Owner's Manual for Measuring Instruments CPS TEMP-SEEKER TM360C. CPS TEMP-SEEKER TM360C 20 pages. Precision thermo-psychrometer multi-channel air conditioning humidity and temperature drop tester

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TECHNICIAN OPERATING TIPS

Experience has shown that accurate temperature readings can be affected by several

factors. Listed below are some of the conditions you may encounter when performing

temperature drop tests.

The pressure that you apply to a temperature probe can affect the reading by as much

as 20°F (-6°C). Try to be consistent when using touch probes, because if you apply

light pressure on the first temp reading and heavy pressure on the second reading

your results may not be accurate.

Air conditioning lines coated with dirt or paint need to be 16 scraped cleaned where

the probe will make contact. Several manufactures use epoxy black paint on condens-

ers and liquid lines that can affect your readings by as much as 30° F (-1°C).

Limited contact area can be a problem if the temperature probe tip is too large. Some

vehicles use a very short evaporator outlet pipe between the evaporator case and the

accumulator nut. In some cases only 3/16 of an inch is available for the probe to make

contact. Taking readings on flange nuts will skew the actual temperature by over 20° F

(-6°C).

Gaining access to the outlet side of both orifice tubes and thermal expansion valves

can be difficult on some applications. Some General Motors and Ford light truck appli-

cations place the outlet tip of the orifice tube just inside the evaporator case. You may

gain access to the pipe by cutting a small section of the evaporator case away with a

hot knife or vibratory cutting tool. After completing the repair job, seal the area with

HVAC Permagum or insulation tape and reinstall the section of the case that was cut

away using plastic welding, if possible.