Saturday, May 24, 2014

Electric fan stuff

cleaning and oiling.
There are times that I would wake in the middle of the night just to check our electric fans. I have this nightmare of waking up with our house burning and being trapped and helpless while my wife and daughter shout for help. 

What's troubling is that this nightmare have happened a lot of times especially in Metro Manila. I have heard on the news that majority of fires during the summer season are caused by overheating electric fans.

I am not an expert on electric motors but many times when electric fans stopped its usually because their fuses gave in. Fuses or thermal protection devices are installed in electric motors to prevent damages caused by overheating through prolonged continuous use. Without this device, an overheating heating motor will continue to work until sparks fly out or until the fan's plastic coverings and wire insulation melted and caught fire. 

Electric fans are not designed for long continuous time of use. Experts advised about eight hours or less of continuous use and then give the fan a rest of about thirty minutes to an hour, enough time for it to cool off.

They don't make them like this anymore, built to last.'s all plastic and disposable.
Heat causes the motor's shaft to expand causing damage to the bushing. Usually a whining sound is emitted and then after that, the blade stops spinning. After cooling it will work again but it will now be prone to stuck ups and overheating.  

Taking your non-working electric fans to your neighborhood repairmen is a risk especially if the technicians are not trained and certified by institutes or the government. 

Some of the things I have encountered with repairmen:

1. One of the first things they do is to remove the fuse and most of the times they do not replace  it and they directly connect the motor to the power thus removing the overheating protection.

2. To save money and have better profit, they use cannibalized spare parts or non-standard parts.

3. They rewind the motor or sometimes they replace the motor with motor from other fans.

Many of our electric fans have been repaired but I usually use them only during the day. But when we are sleeping at night, I use new (or unrepaired) electric fans. At least, I know they still have their overheating protection devices.

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