TM 5-3805-298-23-4
0405
EVACUATION
000405
CAUTION
Moisture will combine with metals in refrigerant system and this will produce highly
corrosive by-products. By-products are oxides, iron hydroxide, and aluminum hydroxide
and they will damage A/C system.
Moisture in A/C system can freeze and damage expansion valve and orifice tube. If there
is water in A/C system, it must be removed.
Failure to follow these cautions may result in damage to equipment.
NOTE
If replacement or repair of component is necessary, refrigerant must be recovered from
A/C system.
If A/C system has lost any charge after long period of time, refrigerant in A/C system must
be recovered.
It is necessary to perform evacuating procedures to remove all air and moisture from A/C
system.
A complete charge must never be given to A/C system without first performing evacuating
procedures.
If A/C system has been left open for more than 30 minutes, A/C system has been exposed
to air and moisture. New receiver/dryer must be installed.
Evacuating A/C system with vacuum pump will boil and remove any water in A/C system.
Remove water from A/C system by evacuating A/C system with vacuum pump.
0405-4
