How To Sevice A Table
Fan
This Hestar table
fan problem was not rotating even if it already switched “On”. You
could hear a sound coming from the motor and when I try turning the
propeller (plastic blade) I found it to be stuck! By right a good
fan when you turn it, the propeller should rotate according to the
force applied on it. It could be the long time of accumulation of
dust that had jammed the motor shaft preventing it from turning
smoothly.
Once the back
cover (motor housing) and the oscillation knob have been
removed, I could see lots of dust and dirt around the motor. I used
a vacuum cleaner together with a brush to clean up the dust. You
could also see a motor starting capacitor ( 2 microfarad 350 VAC ) attached
beside the motor. This is the Metallized Polypropylene Film type of
capacitor.
The function of the motor start capacitor (AC motor capacitor) is
to provide that electrical "push" to get the motor rotation
started. Without a motor starting capacitor (such as when one open
circuit or burns up), when the voltage is applied, the motor will
just sit and hum. But if you were to grab the shaft (or the
propeller) and give it a spin, the motor would (usually) start and
run normally. I do not think the capacitor have problem because the
symptom was the shaft jammed causing it not to rotate.
Anyway I took out
the capacitor and check it with a digital capacitance meter to see
if the capacitance is within range or not. The value
was 1.751 microfarad,
and it is slightly lower then the tolerance (the tolerance
for this type of capacitor is about 10%). If the capacitance
value is too low then I will replace it with a new one.
Please make sure you get a replacement with the same or
higher voltage and if possible with the same capacitance. You
can easily get a motor starting capacitor from any electronic
distributors. I put back the motor starting capacitor and
start servicing the fan.\
First I sprayed
the Philip oil base to the contact that caused the shaft hard to
rotate. The motor shaft immediately rotates (turned by my hand)
smoothly the moment it had oil in it. When I switch the fan “On”
again, the motor start to run! I switch off the fan again and
applied some grease into the back gear (oscillation knob
gears) that controls the fan whether you want it to be “still”
or “oscillate” (don’t use the oil spray in this area because it can
worn out the gear faster).
After everything
was done, I tested the fan and it worked like a new fan! Servicing
the table fan is not difficult and you can try servicing one in
your home. Remember, safety have to come first, make sure you
unplug the AC cable before starting to dismantle the fan apart.
Learn How You Can Become A
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