4
Medium (MED) position sensitivity is
used for chlorine and chlorine based
gases like R12, R22, R123, etc. and will
indicate a 0.1 ounce per year or greater
leak rate. This position supports finding
a 0.5 ounce or greater leak during the
moving probe test as defined in SAE
J1627. It is also useful for locating larger
R134a leaks of one ounce or greater.
Large (LARGE) position is used to zero
in on gross leaks of any refrigerant. If
a large leak is suspected, set mode
switch to
MANUAL
. Adjust
BALANCE
knob
for a sound of 2–3 ticks per second
and slowly approach the test equip-
ment/area. Continue to turn the
BALANCE
knob counterclockwise as necessary to
maintain 2–3 ticks per second. As you
approach the vehicle or equipment, the
gas concentration will increase, causing
an alarm condition. Each time an alarm
occurs, re-adjust the
BALANCE
control.
Continue this process until the leak is
located. Blowing out the test site with
shop air may enable you to locate the
leak more quickly.
Note: After a large leak is located and
repaired, blow out the area again with
shop air, set the unit on the small leak
sensitivity and double check equipment
for small leaks.
Warning! Personal Injury Hazard.
Do not use the H10PA in an explo-
sive or combustible atmosphere. The
ambient atmosphere is drawn through
the probe and through the sensor,
which operates at approximately
1472°F (800°C). The resulting hot
mixture of air and combustible gas
could explode.
