Haier HB21FWRSS Service Manual page 46

power supply circuit have been inversely connected accordingly ,this makes the null line
become a live wire .
G. Stronger vibration and loader noise
1) Refrigerator placed improperly
a) Uneven ground
Uneven ground will cause the refrigerator to be placed unsteadily, causing stronger vibration
and noise during its operation.
b) Leveling screws not properly adjusted
If the leveling screws on refrigerator legs have not been adjusted properly, vibration and noise
will still occur even if the refrigerator has been placed on a level ground.
2) Abnormal noise from compressor
Three suspended spring inside the compressor case are out of balance, and strike against
the case, moreover, the wear of compressor parts may cause noise sometimes.
3) Resonance of tubing and loosening of parts
Improper and compact laying of tubes or the loosening of parts may cause vibration and noise.
4 Large noise of the fan
a)The fan motor is loose;
b)Noise is produced by normal operation of the fan.
c)The impellers are not tightly fixed or eccentrically assembled.
Remedy:
For reason a): Fasten the fan motor.
For reason b) or c): Replace the fan motor or impellers.
5)Inspection method
To find the sources of noise, press the vibration spot with your hand while the refrigerator is
in operation and listen attentively whether the vibration becomes weaker or vanishes. If the
refrigerator has not been levelly placed, put a level meter on its top table and adjust the
leveling screws on its legs. In case noise occurs from the compressor, strike different
locations on the side surface of its case using a rubber hammer or hand hammer with a wood
block in-between so as to determine whether the suspended springs are out of balance or
being seized.
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