How to Tell if a Fluorescent Bulb is Bad – 5 Ways to Find Faulty Bulbs

If your bulb is flickering, it’s an indication that your fluorescent bulb is going to die pretty soon. But is it time to replace?

Time will tell. You must test the fluorescent bulb before considering a replacement. Let’s show you how to tell if a fluorescent bulb is bad.

There are some usual reasons a bulb can go bad, and we can do some quick checks to find out if it’s fixable or a replacement is necessary.

Let’s find out the ways we can check if your bulb has passed its lifespan.

How to Tell if a Fluorescent Bulb is Bad

Quick Checks to Find out if a Fluorescent Bulb is Bad

Check the dark areas at the end of the fluorescent bulb

A long term of use or over aging might cause brownish spot at the end of the bulb. Brownish spots indicate your fluorescent bulb standing at the end of the lifespan.

Though the bulb still has some breath left to spread light for few more days, you might notice reduced brightness from your fluorescent bulb.

Brownish spots will turn into darkness at the end of the bulb.

When you reach this state, you should understand you have only a few days left before you need to replace your bulb.

If only the edges are affected by the darkness, you can flip the bulb to solve the issue for now. What if darkness forms in one side?

Rotating your fluorescent bulb by 180 degrees, from how the bulb usually sits may solve the problem.

Check the pins of your bulb

As you know, two straight pins at both the end of a bulb used as an electrode. Electrodes are the connectors from the source.

Often the pins bend down or misalign, which causes failure to pass electricity. You can check all four pins located at both the end.

You might use a tiny plier to straighten them. If any of the pins seem bent, try to fix it gently. Do not to put too much force while working.

Only a little extra pressure can break the pins which will put an end to your fluorescent bulb permanently.

Test in another bulb frame

Just like the bulb, holding frame can turn bad as well. You can face trouble with your bulb in this aspect also.

You should check your bulb by dismounting it from the existing frame and mount it in another working one.

If the bulb is lighting perfectly in another frame, you should understand your bulb is alright and the previous frame was defective.

Watch your panel box

Having trouble with your fluorescent light? You should check your panel box before blaming the bulb. Make it sure your circuit is in one piece.

You can not expect the bulb to light up with a broken circuit. A long term use can trip the breaker.

If that’s the case, you should push the switch to off position and switch back on. Check out if the bulb lights up.

Use a Multimeter

A multimeter is a machine, used to check the electrodes. If electrodes do not pass electricity from the source, the bulb will not light up.

Electrodes get erosive after a long term use and might stop passing the electricity to the bulb.

The multimeter can examine if the electrodes are passing current or not.

Despite all the method above, cleanliness is another secret to increasing your fluorescent lamps lifespan.

You should clean the bulb pretty often to get the most out of it.

That’s why before you put your money on a new bulb, it’s best to test your current bulb. If your bulb works fine, you may save you some money.

Before replacing your fluorescent bulb, you must check the bulb for once at least.

Often we run to a hardware store and keep repeatedly complaining about the bulb.

The thing you need to understand, a bulb will not light if there are any electrical issues. Checking them before complaining might be a wise decision for you.

What Are The Best Ways to Tell if my Fluorescent Bulb is Bad

Best Ways to Test Fluorescent Lamps

Fluorescent bulb is the heart of the lamp. The procedures we said earlier to test a fluorescent bulb, can also be used to test fluorescent lamps.

Overuse for a long time, bad pins or fixture are the reason for a lamp to turn bad. Constant dust can also cover the bulb and reduce the brightness.

Cleaning the lamp might solve the brightness issue as well. Though, checking the bulb is the ultimate answer to test a fluorescent lamp.

How to Test Fluorescent Bulb Starters

Modern fluorescent bulbs do not come up with any starter. Not so long ago, we had tube-shaped fluorescent bulbs which required a starter.

Starter gets dark along with time just like the bulb. The darkness of the starter indicates its lifetime is nearly over. Some starter comes with a transparent body.

You can plug out and check if any wire has been cut. Due to over-voltage often starter gets burn inside.

Plugging it off and a closer view might solve the issue. Besides, swapping starter with a working one can also tell whether the bulb defects or the starter.


Please enter your comment!
Please enter your name here

Must Read

How to Glue Metal to Metal – 3 Easy Steps and Best Glue

This post has affiliate/referral links. Learn more. When you know how to glue metal to metal, you'll have a handy technique for your DIY crafts...

How to Make Resin Dice with Silicone Dice Molds – In 6 Easy Steps

This post has affiliate/referral links. Learn more. You can learn how to make resin dice as a tabletop games hobbyist, Dungeons and Dragons player, Magic...

How to Clean Retainers – 2 Easy Ways & Helpful Tips

This post has affiliate/referral links. Learn more. Retainers sits inside your mouth so you'll want to know how to clean retainers to get rid of...

How to Make Your Room Feel Bigger with Rugs – 10 Easy Tips

This post has affiliate/referral links. Learn more. Area rugs are a great way to design your floor space. Area rugs can make a room look...

7 Things To Buy That Makes Your Home Feel Nicer Under $30

This post has affiliate/referral links. Learn more. Your home means more to you these days because you may be spending extra time indoors. It's not only...
Save it now!