FAQ: Why Do My Light Bulbs Keep Blowing?

Light bulbs can blow for a number of reasons, and we will try to cover the all the possibilities today in this post. We will also offer some words of advice from the electricians here at Mister Sparky.

1. Cheap bulbs

One reason why your light bulbs might be blowing out often is that the light bulbs you are buying are cheap and low quality. The elements in cheap bulbs are much thinner and any surge of power, however slight, will break them. The cheaper bulbs are not meant to last long and will continue to break at a rapid pace no matter how new they are. Always go for more expensive, better quality light bulbs saves you money in the long run.

2. Loose Connections

A loose connection in the lamp holder can also cause the light bulbs to blow.  When the circuit is not tightly completed, it makes the electricity jump and not flow. When the power jumps, it creates more heat in the fitting than recommended for by the bulb to handle forcing it to blow.

3. Mechanical Vibrations 

Any movement or vibration while the lamp is on will also reduce the life markedly. Check to see if the placement of the lamp is near a room that faces some form of heavy movements like dancing or loud music.

4. High Voltage

Over-voltage of 5% halves the life to about 1000 hours; 10% over voltage will cut it to about 700 hours. A voltage of 250 Voltage for an intended 230 Voltage circuit can cause a significant life reduction and blow the bulb.

What happens When a Bulb Blows?

When a bulb blows the fuse for the lighting circuit will blow or trip also. The reason for a blowing lamp tripping an MCB (Miniature Circuit Breaker) is that the light element gets thinner during its life to the point where it breaks at the weakest point, this point will melt just before failure. The resistance of the overheating element will temporarily be very low causing a current surge which is picked up by MCB’s but not fuses.

How To Fix Your Blowing Bulbs

3 places to check if your light bulb keeps blowing out. Also, always consider buying high-quality energy efficient light bulbs like LEDs.

  1. Your bulb supplier
  2. The wire connections inside your bulb holder
  3. If the spring loaded connectors are working properly inside the bulb holder

For high voltage

  • Put on a dimmer or variable transformer
  • Ask the power company about the voltage problem – is it neighborhood-wide?

As a last resort, you can also check the tightness of the connections in your switch.

Call a Mister Sparky electrician for help, we cover all electrical wiring issues offer electrician services for the entire North Bay Area (707) 723-4066.