24-18 HEATERS AND AIR CONDITIONING - Service Adjustment Procedures
(5) Screw a can of R-12 to the opened manifold valve. Be sure
gasket is in place and in good condition. Tighten refrigerantcan and manifold locking nut to insure a good seal. Do not
overtighten 8 to
11 Nm (6 to 8 ft.lbs.) is sufficient if gasket
is in good condition.
(6) Turn manifold valve (above the refrigerant can) completely
clockwise to puncture the can. This closes the valve and
seals the refrigerant in the can.
Caution
Never heat small cans of refrigerant over
40°C (104°F)as they may explode.
(7) Place the refrigerant in a large pan of water heated to 52°C
(104°F). Place pan of water containing the refrigerant can
on an accurate scale so the amount of refrigerant added
can be weighed. Open the refrigerant manifold valve.
(8) Purge all air from test hoses. Air in the system will be
trapped in the condenser causing abnormally high dis-
charge pressures and interfering with condensing of the
refrigerant.(9) Slightly loosen both test hoses at the gauge set manifold.
Tighten the hoses as soon as the air is purged.
(10)Slightly loosen charging hose connection at gauge set
manifold. This will purge air from the charging hose.
Tighten connection as soon as air is purged.
(I l)With vehicle windows open and hood up, operate engine at1,500 rpm and jump the low pressure switch terminals
located on the receiver drier so the clutch will remain
engaged.
(12)Place air conditioner control on air conditioner and place theblower switch on high.
(13)lf necessary, block the condenser to maintain a discharge
pressure of 1,422 to 1,520
kPa (206 to 220 psi). System
must be charged through the evaporator suction service
ports as follows:
(a) Slowly open the suction service gauge valve.
Meter flow of refrigerant by adjusting, the suciton
service gauge valve so that pressure registered at the
suction service gauge does not exceed 345 kPa (50 psi).Keep refrigerant container upright.
(b) Add refrigerant gas until there is no foam visible at the
sight glass.
Add an additional
170 g (6 oz.)
(c) Close the suction gauge valve.
CautionToo much refrigerant in the system can cause
abnormally high discharge pressures. Care must beused so that the exact recommended amount or
refrigerant is added after foam clears in the sight
glass.(d) Close dispensing manifold valve. Remove test hoses
and adapters from the service ports of compressor,
install protective caps at service ports and reconnect
wiring.(e) Check system performance.
(P.24- 16.)
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