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One of the ceiling fans at home was spinning in the opposite direction (clock-wise) and so was sucking up the air rather than blowing it. I live in a hot climate so we always have the fans spinning in the counter-clockwise direction all year round. I need some guidance on safely correcting the direction of this fan. It's been 8 yrs since I last studied Electrical maintenance and honestly do not recall the wiring diagram.. :)

  • Below is an image of the wiring of another fan that correctly spins in the counter-clockwise direction:

Spins correctly in the counter-clockwise direction

Observations:

  1. Input power supply: Yellow wires to the right
  2. Capacitor: White wires on the left
  3. Black: ?, Red: ?, Blue: ?
  • Below is the wiring of the fan that spins in the clockwise direction:

Spins in the clockwise direction, I need it to spin in the counter-clockwise direction

a. Observations:

  1. Input power supply: Indicated on the right
  2. Capacitor: White wires on the left
  3. Black: ?, Red: ?, Yellow: ?

[UPDATE]

b. Observations:

  1. Swapped the red with Yellow.
  2. Fan remains stationary.
  3. Fan will start to move at constant speed in the direction I apply force in.

Product: Crompton Greaves Ceiling Fan - 220/240 V 50 Hz A.C.. SWEEP 1200mm (No lamp).

Wiring diagram: Could not locate the same. Kindly share any wiring diagrams that could help me better understand the same, Thanks..!

Kindly note: This is an Indian fan and the color codes are different from the US standard.

Color Codes: Phase: Red/Yellow/Blue, Neutral: Black, Ground: Green.

I tried checking with the manufacturer on this, but haven't received a response.. Not all single phase AC motors can reverse direction. [1][2]

Latest updates: We finally got a new fan and the old one was sold to scrap.. So while I am no longer able to test your solutions, I definitely look forward to technical explanation of the problem and possible solution(s). Thanks!

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    On all of the fans I've seen, there's a switch to reverse the direction for you: delmarfans.com/educate/basics/…
    – Andrew Bonnell
    Nov 17, 2013 at 15:07
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    Must be a quirk, which I suppose makes sense as the fan reversal feature only really makes sense in climates with both heating and cooling climate control. If you post a model number, someone may be better able to help you out.
    – Andrew Bonnell
    Nov 17, 2013 at 15:34
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    For reference: en.wikipedia.org/wiki/Induction_motor#Rotation_reversal
    – Andrew Bonnell
    Nov 17, 2013 at 15:40
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    Changing the rotation direction of an AC motor requires the internal motor wiring to be changed.
    – Tester101
    Nov 17, 2013 at 19:24
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    Way late to this conversation, but is it possible that the angle of the blades can be adjusted (instead of reversing the motor)?
    – DA01
    Aug 5, 2015 at 3:48

6 Answers 6

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With another clockwise fan from the same maker, I was able to reverse the direction by interchanging the yellow and black wires as some answers here indicated. The explanation as I understood is that the rewiring changes the winding with which the capacitor is in series and hence the starting direction is inverted.

In 3-phase motors, each of the three stator windings carry a current out of phase with others and the phase difference generates the rotating magnetic field required to cause the motion. With single-phase ones, a phase difference is engineered by splitting the single phase current into two stator windings and putting a capacitor in series with one of the windings so that there's a 90° phase difference between the currents in the two windings. This page on electric motors explains the concept with illuminating animations.

The following figure shows my guess, based on the above information, at the internal wiring of the clockwise spinning fan whose image is posted in the question, for clockwise and anti-clockwise rotations.

Capacitor start induction motor wiring

A point to note here is that single-phase AC itself produces a changing magnetic field - though a pulsating one, not a rotating one. But this pulsating field can be resolved, as per the double field revolving theory (the link has an excellent video of the workings by the way), into two revolving fields rotating in opposite direction to each other. These two fields produce an equal but opposite torque. On a static rotor, they'll cancel each other out. But an initial rotation makes torque in one direction greater than the other and starts up the fan.

This is what, I believe, happened when the OP switched red and yellow wires on his fan. The result was that the capacitor was in series with both windings => there was no phase difference in the currents in the windings. When he added a slight initial rotation, the fan continued spinning in the nudged direction.

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Ceiling fans either have a switch to change the direction, or a sequence to change it. If there is no switch.

  • Set the fan to the slowest setting.
  • Turn the fan on, off, then back on quickly.

When the fan comes back on, it should come on in the opposite direction.

switching sequences may vary from manufacturer to manufacturer. Consult the owners manual for proper sequence.

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  • Hi @Tester101, Thank you for your answer. Above steps didn't work for me.. Waiting for a reply from the manufacturer as they didn't seem to provide a wiring diagram on their site.
    – Kent Pawar
    Nov 17, 2013 at 19:38
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An simpler way: just move the supply connection that goes to the capacitor (in this case, W & Y), to the other side of the capacitor (W & Bk). This motor is known as a 2 phase motor. The 2 windings are identical. The current through a capacitor leads the voltage by 90°, so the current (& magnetic field) in the poles of the one fed through the capacitor leads, then shifts to the poles of the other one in between, creating a spinning field which the rotor follows. If you connect the supply to the other side of the capacitor, the other winding leads and the field spins the other way. You can even put a changeover switch to switch the supply from one side of the capacitor to the other to make it reversible. If you get the leads mixed up, just measure the resistance between them. The 2 that go to the capacitor will have double the resistance between them. When you swapped the red & yellow leads, the current was only going through 1 winding L1 in Hemantha's diagram and, with only an alternating field, the motor couldn't decide which way to go.

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This is what I'd do:

  1. Leave the terminal of the capacitor which is connected to the supply as it is.

  2. The other terminal is connected to one end of the winding. This needs to be disconnected and connected to the other end of the winding.

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If you have a remote controlled ceiling fan with no reverse switch don't worry if you lost the remote. You can reverse the direction of the fan manually. Remote controlled fans are controlled with a sequencing code from the remote which is simply controlled by cutting the power on an off. To reverse your fan direction turn off the power switch to the fan. Take a broom and hold the blades still. Flick the power on and off a few times leaving the power off. Wait a few second then turn the fan blades in the direction you desire then turning the power back on to the fan. The fan should now continue in the direction of you choice.

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    The fan in question isn't one controlled by a remote control nor is it a reversible fan.
    – DA01
    Aug 5, 2015 at 3:50
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You can change your rotation by changing the input of yellow to black wire; it will change the direction of rotation.

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    Another (now deleted) answer already suggested that. Please explain what this does and why it would work. Thanks!
    – Niall C. ♦
    Mar 10, 2015 at 14:22

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