Why Light Flicker When AC Turns On

After you finish installing an AC, it’s common to experience slight hiccups in performance when starting it for the first time. But, have you ever experienced the lights in the house flickering when the AC comes on?

Why do lights flicker when the AC turns on? Is this a cause for alarm or an everyday occurrence when an AC is running? These questions are some of the first that come up for concerned homeowners.

Understanding why the lights flicker when the AC turns on is important, as it can be a minor issue or a major problem depending on the circumstances. This article will help you understand why this happens and when you have to call an HVAC expert like Direct Air.

Why Do My Lights Flicker When My AC Turns On?

It is not uncommon for lights to flicker when you use your AC to cool your home or office. While it’s easy to panic the first time you see it, in most cases it’s not a serious issue. You’ll mainly experience flickering or the lights dimming for only a few seconds before working normally after the AC starts up.

As for why it happens, it’s important to understand that an AC is a piece of powerful equipment dedicated to cooling your home. Such appliances require lots of energy to keep running until you shut them off. While modern AC systems are energy efficient, they still require a certain amount of electricity to work correctly.

Usually, most homes limit the amount of electricity coming into power appliances and lights. When you have larger appliances like the AC system, these will require more energy to power up. So, each time your AC system turns on, it needs this amount of electricity.

As the AC system draws more energy, it pulls more power away from other functions. This includes the lights that now get less energy. Flickering occurs, but only for a second or two, and then you have bright lights once more in your home.

There’s a problem if the flickering is constant or the bulbs remain dim longer. Different issues can cause your lights to keep flickering or remain dim while the AC is running.

Is It Okay for My Lights to Flicker for Longer When My AC Turns On?

These questions are quite common with AC unit owners – why do my lights flicker when the AC turns on? And is it a big issue?

Well, as mentioned earlier, if it flickers for a few seconds, it’s not a big issue. But if it’s frequent and lasts longer, you need to ascertain the cause.

So, why do lights flicker when AC turns on? Here are the major causes:

1. Overloaded Panel

When the flickering lasts just a few seconds, that’s okay. But, when the occurrence happens more often, and for longer, every time the AC is on, something is wrong. One issue you could be facing is an overloaded electrical panel.

When there’s an overload in your electrical panel, the lights will do more than a little flicker. You’ll even hear a sizzling noise as the flickering happens, and lights may turn off completely. If this keeps happening, you run a greater risk.

This is why it’s crucial to ensure your AC has its own circuit for better function. Adding other big appliances to the same circuit as your AC often overloads the panel. If you have an older home with an aging electrical panel, know it will struggle with modern appliances, including new ACs.

The minute the flickering lights start to go off, and you hear the noise as this happens, it can be dangerous. An overloaded circuit puts you at great risk of shock or even an electrical fire.

The minute you notice this issue, start unplugging big appliances that may be causing the overload. After that, contact an HVAC company for assistance on this issue.

2. Electrical Wiring Problems

Wiring in your home grows old and gets damaged or frayed. While it’s normal for the AC to cause lights to flicker, there are most likely electrical wiring problems if this keeps happening rapidly.

If every time your AC turns on, the flickering keeps happening and won’t stop for some time, there are loose or charred wires somewhere in your home. Wiring problems cause an energy flow issue to your light bulbs. So, since there’s already an energy flow drop as your AC kicks in, your lights flicker more than usual.

As the electrical problems worsen, you notice a dimming in your light bulbs that won’t reverse. Electrical problems are dangerous, and you should never ignore them when you notice extensive flickering. Call an HVAC contractor immediately to offer proper solutions.

2. Faulty AC Capacitor

Every HVAC system has a capacitor. As your AC turns on, it’s the role of the capacitor to deliver that jolt of energy to get it running. When this happens, the lights only flicker for a second or two and then resume normal brightness.

However, if you have a faulty capacitor, your light bulbs grow dimmer when the AC turns on. At this point, your capacitor struggles to give the AC motor the energy it needs to kick on. Since it’s an energy storage device, it is losing its ability to store the power your AC needs.

If you don’t have a dedicated AC circuit, more energy goes to other appliances in your home. This is why your lights will dim more than the usual simple flickering. The right step is to call an HVAC expert to fix the problem.

How Do I Stop My Lights from Flickering When My AC Turns On?

It’s not bad for lights to flicker as your AC turns on. However, it’s prudent to ensure the AC has its own circuit for better energy distribution. Speak to your HVAC contractor about this and change the circuit in your home if it’s not ideal for modern appliances and systems.

Another solution is upgrading the wiring in your home. It’s quite common for wiring to age and even come loose with time. An upgrade will benefit a modern home using the latest appliances and Heating, Ventilation, and Air Conditioning technology. Often, the same company you hire to work on the AC has a dedicated team of electricians who can help.

Also, if the issue is a faulty capacitor, it’s time for an upgrade. Leaving a weak capacitor in your AC can lead to bigger problems with energy flow to your unit as it turns on. This causes the AC to shut off completely. Therefore, reach out to your HVAC expert to replace it pronto.

Key Takeaway

It’s not unusual to ponder why lights flicker when AC turns on. This is common since the units need more energy to start cooling your home. However, there’s a problem if the flickering lasts and even causes lights to dim longer.

Turn off all appliances sharing the AC circuit and contact an HVAC expert to take a look immediately.

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