WD Catalog 2018

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Chapter 6 - Service Tools & Their Use
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Halide Leak Detector (R-12 Only)
A Halide propane torch leak detector can be used to find system
leaks as low as five ounces per year. It includes a propane tank and
torch assembly. The torch assembly includes a control valve and
tube, pickup hose, orifice at the top of the tube, and copper reactor
plate. A chimney surrounds the orifice and copper plate and has a
window cut out. The chimney shields the propane gas flame. You can
analyze flame color through the window.
In use, ignite the propane and adjust the flame to heat up the
reactor plate. The burning propane gas sucks air up the pickup tube
(the oxygen in the air also burns with the propane). To detect leaks,
move the pickup tube slowly about the AC system. Take care to move
the tube below potential leak points because R-12 is heavier than
the air. Any R-12 present is drawn up the tube and burned. When R-
12 is present in the flame, the copper reacts with it and the flame
changes color. Figure 6-7 illustrates this leak detector and method.
The flame colors are described.
HALIDE LEAK DETECTOR FLAME CONDITION (WAIT TILL REACTOR PLATE IS
CHERRY RED BEFORE CHECKING SYSTEM FOR LEAKS)
TORCH FLAME
AREA
PICKUP HOSE
PROPANE TANK
PALE BLUE
NORMAL FLAME
PURPLE/BLUE/VIOLET
BIG LEAK
LIGHT GREEN/YELLOW
SMALL LEAK
COPPER REACTOR PLATE
CLOSEUP OF CHIMNEY CONTROL
VALVE
WARNING An open flame in your shop is dangerous. The Halide
leak detector should be used with care. Be sure there
is adequate ventilation to carry away any fumes from
the torch. Remember that refrigerant changes to a
poison gas when burned.
Electronic Leak Detector
Electronic leak detectors are safer than the Halide system and about
ten times more sensitive. Some designs can detect an R-12 or R-134a
leak as low as one half ounce per year. There are two types of
electronic detectors, positive ion and negative corona. These techni-
cal terms, positive ion and negative corona, are used in describing
the electronic elements and their function in these detectors. The
negative corona type detector has a longer service life and requires
less power.
Figure 6-7
The halide leak detector and
parts are described. You can
use it to detect R-12 leaks
as low as five ounces per
year. There are three draw-
ings of chimney/reactor
plate/flame conditions to
show you how the detector
works to indicate a leak.