Caution: Failure to maintain a neu-
tral atmosphere within tubing during
brazing can cause copper oxidation,
producing harmful chemical reac-
tions in the compressor lubricating
oil, and a deterioration of the refrig-
erant resulting in harmful acids and
general contamination of the system.
Apply heat with an acetylene gas
torch, using a neutral to reducing
flame (a greenish) feather extending
from the tip of the inner cone indi-
cates a slightly reducing flame.)
Heat the fitting and tubing evenly
over the full circumference of the
joint, keeping the torch flame in mo-
tion to assure even distribution of
heat. Test the temperature by touch-
ing the edge of the joint with brazing
alloy. Do not apply the flame to the
alloy. When the alloy starts to melt
and run, the heat is right for brazing.
Caution: Use a piece of asbestos
sheeting to protect other portions of
the system from flame damage during
Feed brazing alloy cautiously. Alloy
will flow freely at right tempera-
ture but will burn when too hot.
When joint is full, brazing material
will appwm in a
around the edge of the fitting.
Be sure that some part of the system
Wipe excess material from joint with
rag or brush while joint is still hot.
Inspect joint to make sure it has
97. Charging the System
The system must be charged witih the cor-
rect amount of Refrigerant-22. The correct
amount is 16 lbs. Make charging connection
as shown by figure 37. Charge by the follow-
a. Connect a bottle of Refrigerant-22 to the
charging panel (figure 37) and open valves
A and B. Valves C and D should remain
b. Open the valve on the refrigerant bottle
to allow gas to enter the system until the pres-
sure is equalized with that in the cylinder.
Caution: The compressor must not be oper-
ated before step c has been completed.
c. Close valve A.
d. Operate the compressor and slowly
charge into the system, After sufficient refrig-
erant has been added, the refrigerant will start
building up in the receiver. At this paint the
discharge presure will continue a steady rise.
When this condition exists, the unit is fully
Note. If the unit is overcharged, the refrigerant
is left open to atmosphere during
Otherwise pressure may
build in the system and blow brazing
material from the joint.
will fill up the receiver space and back up into the
condenser space. If this happens, a sudden and ex-
cessive increase in discharge pressure will be noted.
If this happens, bleed the entire charge, and recharge
(paragraphs 95 and 97).
Section II. COMPRESSOR
The hermetic compressor is hermetically
sealed, and if found to be dafective, it must be
removed from the refrigerant circuit and a new
compressor installed. The new compressor will
have been charged with oil and nitrogen gas
as a holding charge.
a. Replacement. Remove the compressor as
shown by figure 28.
Using a wire brush or crocus cloth,
clean the system suction and dis-
Crack the flare nut on the charging
valve of the new compressor to re-
lease the nitrogen-holding charge
then retighten the flare
Remove any charging fittings or caps
from the compressor and prepare the