Repairing Neon Signs: 3 Common Causes And Solutions For Flickering Lights

9 March 2016
 Categories: , Articles


If you're looking for a business sign that simply can't be ignored, you can't go wrong with neon signs. Ever since neon signage was introduced to the U.S. in 1923, it has made a huge impact. Neon signs are not only attention-grabbing, but they can be seen in all weather conditions. Neon lights can even cut through fog. With that being said, if your neon lights are flickering, not only is your sign not grabbing any attention, but it is also in danger of needing expensive repairs if the flickering issue is not dealt with immediately. This article will take a look at 3 common causes and solutions for flickering neon lights.

Shake the Sign

If you have just recently purchased the neon sign, there's a good chance that the flickering isn't caused by any damages. The argon in neon signs require mercury in order to glow brightly. Mercury in new neon signs may have yet to turn into vapor. If that's the case, leaving the sign on for a few days should solve your flickering problem.

If you don't want to wait a few days, you can turn the sign off and shake it vigorously to see whether you can loosen up the mercury, so that it becomes vapor quicker. Be careful when shaking your sign, as you don't want to damage the bulbs or any other important components.

Inspect the Neon Glass for Cracks

Small breaches, like cracking or arching, in the neon light bulbs can also cause flickering to happen. Generally speaking, when this happens, the section of glass with the breach will fail to work, and other tubes that are not breached but wired in-line will start to flicker. This is due to the fact that the gas cannot accumulate quickly enough within the bulbs for them to stay brightly lit.

If this is the case, the section of the glass that has been breached will need to be replaced. If the breach is small enough, a repairman may recommend re-pumping the sign with gas instead while putting a patch on the breached area. Be especially careful when handling bulbs with breaches in them because they will be particularly fragile and susceptible to breaking apart.

Check for a Faulty Transformer

Another common cause of flickering lights is the presence of a faulty transformer. The transformer is responsible for reducing or increasing the voltage of an alternating current, so that it is compatible with the current requirements of the neon sign. If the light bulbs are in good condition, then there's a good chance that you have a faulty transformer in your hands. If this is the case, you will have to replace the transformer. Be careful when purchasing a new replacement because the specifications of the new transformer must exactly match the original transformer label or the sign will not light up flawlessly.

While the transformer is often located at an easily accessible location of the sign, you need to be extremely careful when handling the transformer. Make sure you unplug the sign before you even attempt to take a look at the transformer, as a typical transformer has an output of 4,000 to 12,000 volts. That's enough to fatally electrocute a person.


There are many other reasons why your neon signs may be flickering. If you can't figure out what is causing the flickering, you should have a professional sign repairperson take a look, as there are a million other possibilities. Neon sign repairs can generally be completed quite quickly, and your sign will once again be grabbing the attention of people passing by.