AUX E Series, Service Manual

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AUX air conditioner service manual
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burned or components can’t start up. So clearance scope between pistol and cylinder is very small. For
Dia
φ
50mm cylinder without pistol ring, fit clearance shall be within 0.011~0.018mm. If pistol or
cylinder wears out severely, when pistol compresses and exhaust the gas, a part of gas in cylinder will
leak into pump shell through clearance, so compressor can reach its original discharge capacity;
b) Gasket rib of cylinder cover is cracked (reciprocating): There’s a rib on the middle of gasket and it
separates and seals discharge cavity and return gas cavity, preventing high pressure (discharge) gas
from flowing to gas return cavity, and causing a part of gas being short-circuited. If a part of rib is
broken, some gas will be short-circuited, and exhausting quantity of compressor will lessen. To avoid
this type of fault, apply anti-florin rubber on two sides of steel rib. If asbestos rubber gasket is used,
risk of fault like this will be very high.
c) Severe leakage of gas valve(including rotary type): If discharge and return gas valve blades can’t
match tightly with valve line on the valve plate and there’s certain seam; when valve discharges or
returns gas, some gas will leak out from seam, and discharge capacity of compressor will lessen.
Follows are Main factors for this kind of faults: 1) system is not clean enough, there’s some dirt
flowing with refrigerant. Dirt sticks to the valve line and valve blades, when valve blades run,
abrasion of valve blades and valve line will speed up, and sealing performance will lessen gradually; 2)
discharge temperature is excess high often and so refrigerant produces particles, which sticks to valve
structure and damages tightness of valve; 3)slightly liquid hammering often happens in the system,
due to the impact of liquid, valve blades are deformed or damaged, or abraded severely, so tightness of
valve structure is decreased; valve plate has been liquid hammered severely, gas valve is damaged and
valve blades are broken, so that tightness of valve is severely damaged.
d) Crack of exhaust tube in pump shell(reciprocating). To the compressor with unbalanced
reciprocating, pump body librates sharply, exhaust tube will be cracked or broken and refrigerant
steam will circulate in pump shell; steam can’t be exhausted outside pump shell, so refrigerating
capacity of the system is almost zero.
The same symptoms of the foregoing four faults are: discharge pressure drops, return gas pressure
rises, and pressure difference between return gas and discharge pressure becomes relatively low or
very low, or becomes almost zero in the serious condition. In the normal condition, pressure difference
shall be very large, pump shell shall be hot in various degrees, and some discharge tube will be very
hot.
②
Compressor can’t run normally
When compressor is switched on, motor will produce buzz in pump but fails to run. After 3~5 seconds,
heat protector trips and cut off the power supply. This symptom is resulted by following faults:
a) Main journal and bearing or big end and crankpin burn out and melt because of lack of
oil(commonly called coherence) , for oil in compressor is not enough or oil nozzle is blocked by
pistol;
b) Air valve is broken and broken valve blades fall into cylinder and block the pistol, so valve can’t
reciprocate;
c) Connection rod is broken and motor can’t be driven.
③
Motor in compressor is broken.