Heavy accumulation of dust or dirt on the blades can cause a ceiling fan to shake. Wipe clean the blades carefully with a damp cloth. Avoid applying too much pressure on the blades because doing so will force the blades out of alignment.
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If the blades of a ceiling fan are out of alignment, the fan will definitely shake. For a ceiling fan with four blades, directly point each blade one after the other at yourself and ensure that it aligns with the blade directly across from it. If that is not the case, gently bend the blade holders to bring the faulty blade into proper alignment.
In case the ceiling fan you are fixing has five blades, you just need to make sure that all blades are equidistant from each other. If a particular blade is closer to its right hand blade than the left one, gently bend its blade holders to make it equidistant from its neighbouring blades.
Warping of blades can also cause a ceiling fan to shake. To check for warping, unscrew all the blades from the fan. The must snugly fit when placed on top of each other. If a particular blade does not fit properly, it means that the blade is warped and you will have to replace it.
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With the ceiling fan hung in position, measure distance from each blade’s top to the ceiling. Make sure that the readings are same in each case. If a particular blade top is farther or closer to the ceiling than other blade tops, bend it upwards or downwards. Again, apply just the right magnitude of force.
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In none of these techniques work, the blades of your ceiling fan must be out of balance. Install a specialised fan balancing kit to balance the blades. To properly install a fan balancing kit, read the instructions manual that came along with the kit.
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