What’s Inside? “Heller” Pedestal Fan

I noticed my pedestal fan was beginning to make some weird noises, and decided it needed some new grease, or else it would become a really good electric rattle… Here is how to get inside one of the cheapest and simpler electrical appliances in your house. Mine cost $2 since it was the last one left and Winter was approaching, so they were selling heaters instead 🙂

Tools needed – Phillips screwdriver, flat screwdriver, pliers or small wrench/spanner, triangle bit (check if your fan has any “security” screws – you can get security bit sets for cheap these days), grease (or Vaseline), something to apply the grease – pop stick, latex glove, or just a finger if using Vaseline.

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Firstly, there is one thing you should check to see if you can remove it, or else you will not be able to get inside. It is the little push/pull knob on the top of the fan that turns the oscillating function on or off. The knob is held on by two plastic hooks/clips. You can use a thin flat screwdriver to try and lever one of the clips out, and pull the top of the knob in the opposite direction. If you’re lucky the clip won’t break off…if it does, then you can just wrap some tape around the part where the clips are to make sure the remaining clip holds when you replace the knob later on.

If you’ve gotten past that little problem, then the rest is fairly easy. You take off the front mesh guard by releasing the clips and any screws holding it on. The fan blade is probably held on by a large plastic “nut” that unscrews in a clockwise direction – opposite to a normal screw. The blade then just slides off.

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The rear mesh guard is held on by an even larger plastic nut which has finger holds. The assembly slides off. The next step is to remove the triangle bit screw holding the rear casing. You can now undo the 4 screws holding the front plastic motor guard on (this step may be unnecessary but I took it off anyway). Undo the rear screw that connects the metal beam to the plastic oscillating mechanism.

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Once all the coverings are removed, you will see the motor in its bare form.

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Remove the three screws holding the oscillating mechanism to the motor. The black rectangle thing is a capacitor to improve the power factor of the motor. Basically the motor is a very inductive load since it has a lot of coils, and power is wasted unless there is a capacitor connected to make the load closer to a pure resistive load.

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Once the plastic oscillating mechanism is removed, you can put a nice big blob of grease inside it, although mine didn’t really need it.

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Next, you can remove the nuts and bolts holding the metal peices of the motor together – use the pliers or wrench to hold the nut while unscrewing the bolt. Make sure to keep the washers. The back shell and bearing should slide off pretty easily. You can move the “stator” (coils and metal laminate) to one side. Note the wires are on the back side of the stator. If you put it in the other way, the fan may spin backwards…

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This stator is most likely a “squirrel cage” since it kind of looks like a hamster wheel. Perhaps the inventor of this thought that “hamster wheel motor” sounded silly.

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The rotor should now be able to slide back and forth, allowing you access to the front shell and bearing. Put some grease on the shaft on either side near the bearing, then spin the shaft while moving it back and forth to make sure the shaft and bearing are properly lubricated. This particular kind of bearing is called a sleeve bearing because it only uses a “sleeve” of lubrication between the shaft and cylinder wall. It is cheap and works well for low load applications like this fan.

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Add some more grease to the back shaft. Replace the winding assembly noting how the wires are to be at the back side. Replace the back shell, trying to get the grease into the bearing by rotating and moving the shell back and forth. Bolt it all back together – I managed to get my nuts and bolts back to front, but it doesn’t matter in this case 🙂

Now you just have to do the steps in reverse order to re-assemble the fan – put the oscillating mechanism back on (you may have to rotate the shaft just a little to make it fit correctly), then re-attach the beam to the oscillating mechanism. Screw on the front plastic guard, then the back casing. Put the rear mesh guard on with the “even larger” plastic nut. Slide on the blades and tighten the large nut. Re-attach the front mesh guard. Click the osc. control knob back into position – you may want to check that your fan works first!

Finished

It works! I left it on the fastest speed for a little while since I used wheel bearing grease, which may have been too thick, but it works with no weird noises now! 🙂

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4 responses to “What’s Inside? “Heller” Pedestal Fan

  1. thanks for d insight……….would have preferred this article with a detailed schematic wiring diagram of the stator and speed control switch of this model of heller pedestal fan,anyway.

  2. I’m not so sure on the “main running coil” but they probably use 8 coils as a way of getting smooth operation while keeping enough speed for the fan blades. More coils means the motor will have a lower maximum speed I think.

  3. strange…d stator of typical single phase
    nduction motor has only four coils in d textbooks.y s dis damn stator having numerous coils( at least 8)..which of these freaking numerous coils is the main running coil?

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