TM 5-6115-586-34
psig minimum pressure reading on gauge GA1. If
Do not attempt to operate the leak-
pressure does not increase to 15 psig minimum charge
detector at voltages other than
refrigeration system (para (c) below).
those specified on the rating plate
since damage to the detector may
result.
4. If gauge GAI indicates 15 psig, or more,
proceed with leak check as outlined in steps 5 through 10.
Caution
Note
Do not place probe in a stream of
Screw is for shipping and storage
refrigerant and do not blow
purposes.
Replace screw after
cigarette smoke into the probe
using detector.
since either will drastically shorten
5. Remove screw from cap on reference leak
element life.
and allow 15 minutes (minimum) for leak rate to stabilize.
Note
6. Connect power cord to power supply outlet
Variations in line voltage may
on service unit.
cause erratic operation of the leak
detector resulting in reactions
Note
similar to those for atmospheric
Contamination of the testing area
contamination. If voltage variation
may cause erratic operation of the
is suspected, utilize a voltage
leak-detector. Contamination can
stabilizing device. Note. If the air
occur when the leak in the
flow ball does not rise, tap the
refrigeration system is very large
probe tip lightly to make sure ball is
and where there is little or no
not sticking. If ball still does not
ventilation in the testing area.
rise, replace detector.
where excessive amounts of
7. Check for sufficient air flow by pointing tip
refrigerant gases are used. The
of probe downward and observing air flow ball in probe. If
leak-detector cannot differentiate
air flow is correct, air flow ball will rise and float above tip
between
atmospheric
of probe.
Also, in a highly contaminated area,
8. Place sensitivity switch in either HIGH or
the flash rate will be unstable, and
LOW position.
it will be impossible to adjust the
9. Adjust flashing rate of lamp in probe by
balance control.
Under these
rotating balance control knob until lamp just ceases to
conditions leak detection would not
flash.
be possible.
A contaminated
condition can be greatly reduced
10. Hold probe as closely as possible to the
by ventilating the area or isolating
area being checked and move tip of probe approximately
the area to be checked.
one inch per second along seams or joints suspected of
leaking. When a leak is located, the lamp in probe will
Warning
flash as long as probe is held at the leak.
Do not use leak detector in an
(b) Evacuation procedure. To evacuate the power
explosive
or
combustible
plant refrigeration system, refer to figure 2-3 and 2-4 and
atmosphere. Ambient atmosphere
proceed as follows:
is drawn through the probe and
over the element which operates at
approximately 1800 F (982 C).
1. Open service valve on power plant
refrigerant receiver and compressor suction purge valve
The resulting combination of high
on compressor, allowing liquid refrigerant to vent from
temperature and an explosive or
system.
combustible
atmosphere
may
cause an explosion resulting in
2. When venting stops, attach vacuum hose
severe injury or death to personnel
(ten feet in length) to bulkhead fitting F5 on service unit
and damage to equipment.
and to valve on power plant refrigerant receiver as shown
Caution
2-8