Why Do My Lights Flicker When My AC Turns On?
Many people find their lights dimming or flickering when the air conditioner turns on. A normal electrical occurrence that many homeowners experience, and if you are experiencing a power outage, this can indicate that things need attention. The initial step toward finding the answer to “why do my lights flicker when AC turns on” is understanding why this happens.
Understanding the Problem
When your air conditioner turns on, it draws a significant amount of electrical current to power the compressor and fan motors. This sudden surge in power demand can cause a temporary voltage drop in your home’s electrical system. When voltage drops, your lights receive less power than they need to operate at full brightness, causing them to flicker or dim momentarily.
If the air conditioner is old or the weather is hot and the air conditioner is running continuously, this problem can be observed clearly. Flickering happens for just a few seconds as electricity stabilizes in your home. But flickering can indicate underlying wiring problems or panel problems.
The National Electrical Code (NEC) [a][b][c]has been formatted so that most of the U.S. adopts it for voltage drop:
Why Do AC Units Draw So Much Power?
Air conditioning systems use more power than any other appliances in your home. A normal central AC requires 15 to 25 amps upon start-up, compared to the steady draw once it’s running. Inrush current is referred to as the starting load, which is way higher than the normal load.
One reason for the high demand when starting the compressor motor is to overcome the initial resistance and get moving. When the engine is running, it takes less power to keep it running. The issue is nothing to worry about, as almost all AC devices will see a spike in current draw at startup. The important factor is that your electrical system is properly sized. In older homes, a problem you may run into is degradation of the wiring in the home.
Current Type
What It Means
Typical AC Behavior
Why It Matters
Inrush Current (LRA)[d]
The initial surge of electrical current when the compressor starts
Residential central AC units typically require 15–25 amps during startup.
Higher current is needed to overcome the compressor’s initial resistance and get the motor moving.
Running Current (RLA)
The electrical current is used after the compressor is operating.
Current demand drops significantly once the compressor is running.
The compressor requires less power to maintain operation than it does to start.
Common Causes of Light Flickering
If your home’s electrical panel isn’t large enough to handle the total electrical load of all your appliances, flickering lights when the AC turns on are inevitable. Older homes often have 100-amp service[e][f][g], which may be insufficient for modern appliances. When the AC demands extra power, the voltage drops for other circuits, causing lights to flicker.
If your electrical panel is loose or corroded, or your connections between your meter and the panel are loose or corroded, electrical resistance increases. When high-demand appliances are turned on, the voltage drop is substantially increased due to this particular resistance. The wiring might have developed a fault over time.
Some older electrical panels may have design flaws that can cause them to become susceptible to voltage fluctuations. An upgraded panel could fix your flickering issues if you have an old panel in your house.
According to the National Electrical Code (NEC)[h][i], larger homes that have heavy power loads such as electric heating and upgrading future circuits should use a 200 amp service or greater.
When your AC is pulling large amounts of current, and your house is located far from the utility company’s main line, the voltage drop over that distance becomes significant. Although it is not very common in urban areas, rural places may face this problem considerably.
Your lights may flicker due to improper installation of your AC. Several problems may occur if the unit is not connected to a dedicated electrical circuit or if other high-power appliances share a circuit. It is better for each AC unit to have a dedicated circuit to avoid interference with other appliances.
When Flickering is Normal vs. Problematic
It is normal if your AC first turns on and there is a flicker for a second or more; you will be safe. This indicates the short time period of voltage stabilization as the electrical system accepts the new load.
Call a licensed electrician immediately if you observe:
Solutions to Stop Light Flickering
Quick Fixes and Temporary Solutions
If you have light flickering but can’t replace your electrical system at the moment, there are several temporary solutions offered to reduce flickering:
Refrain from using high-power devices simultaneously while the AC is on. Thus, the electrical loads will be reduced, and hindrances to the voltage will be prevented. If your AC is off or set to reasonable levels, you can switch on your dishwasher, washer/dryer, or electric oven.
If your system offers programmable features, make sure to program it to gradually ramp up rather than starting at full capacity. This spreads the power draw over time so there is less impact on voltage.
LED bulbs do not flicker as easily due to minor voltage fluctuations as incandescent or old fluorescent bulbs do. If you replace your lights with quality LED bulbs, flicker may become less noticeable.
The flickering can be worse if there are loose connections within the electrical panel or outlets. Get the help of an electrician to check and tighten the connections. This minor maintenance could solve the problem without much of an upgrade.
For specific appliances like televisions or computers, plug them into voltage stabilizers or uninterruptible power supply (UPS) units to protect them from fluctuations.
Permanent Solutions
A dedicated circuit for the air conditioner is one of the most effective solutions. This arrangement prevents the AC from being powered by the same source that lights and other appliances use, which causes voltage to drop and causes them to flicker.
If you have 100-amp service in your home, boosting it to 200 amps can give ample power for your appliances. This solution prevents flickering with AC applications, as well as other electrical applications, in a more complete way.
Get a licensed electrician to inspect your house’s wiring for corrosion, damage and loose connections. By replacing faulty wiring, proper voltage can be delivered throughout the home.
For certain AC systems, the use of a soft starter or variable frequency drive (VFD) may limit inrush current. Instead of giving a sudden surge, these gadgets gradually increase power to the compressor motor. Thus, it reduces the drop in voltage that causes flickering.
The inrush current of older air conditioning equipment is higher than that of new, energy-efficient models. If you install a modern AC unit with a better energy rating, it will reduce electrical load on your system and reduce flickering.
Your utility company can install a voltage regulator or upgrade their lines to your home if you live far from their lines in some instances. Get in touch with them to talk about the problem.
Prevention Checklist:
✅ Schedule yearly maintenance with a qualified HVAC technician for your AC.
✅ Your panel should be inspected by a licensed electrician within a 3- to 5 year period.
✅ Every month, check for loose connections in sockets and switches.
✅ Do not operate high-wattage appliances concurrently.
✅ Keep an eye on the electrical bill for extra use.
✅ Ensure that the vicinity of your electrical panel is neat.
✅ Install surge protectors for sensitive electronic devices.
✅ Replace old incandescent bulbs with LED bulbs throughout your home.
✅ Have your AC unit installed by a professional on a dedicated circuit.
When to Call a Professional
Do not ignore electrical problems or try to do it yourself. If you still want to know, “Why do my lights flicker when my AC turns on?” Hire an experienced electrician. Call a licensed electrician if your lights flicker when your AC turns on.
Prevention and Maintenance
To prevent electrical issues and light flickering, maintain your air conditioning system properly. Schedule regular maintenance with a qualified HVAC technician to ensure your unit operates efficiently and doesn’t draw excessive current due to wear and tear.
In addition, do not use high-powered devices simultaneously. Do not use excessive power-drawing electric heaters, ovens, and water heaters along with your AC. Using such devices with the AC increases the load on the wiring.
Get in Touch with COOL-AID CO. Immediately for a Better Solution!
It is common for lights to flicker when the air conditioner is turned on, but it can be fixed. A short flicker is generally nothing to worry about, but if you’re noticing flickering happening constantly or if it’s severe, there’s likely a problem with your home’s electrical system. It could be an undersized panel, faulty wiring, or an improperly installed AC unit, but solutions are available. Get in touch with COOL-AID CO., which has a team of licensed electricians and experienced professionals who can determine the cause and fix the problem.
When you act promptly, your home’s electrical system can keep up with your use of your air conditioner comfortably and safely. If you do not solve this problem now, it could lead to something worse in the future.
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[a]Source link, incase u want to link them: https://energycodeace.com/site/custom/public/reference-ace-2013/index.html#!Documents/84voltagedrop.htm
[b]_Marked as resolved_
[c]_Re-opened_
Ok @danny.djs.seo@gmail.com
[d]Source incase u want to link: https://industrialmonitordirect.com/blogs/knowledgebase/motor-inrush-current-vs-locked-rotor-amps-the-difference?srsltid=AfmBOopvfGZnqLvMilfBVOrfn48zh0Apw2eVBmsLBR8-QNeAjdEnMNk0
[e]source link incase u want to cite them: https://www.energy.gov/sites/default/files/2021-08/bbrn-peer-cooling-081221.pdf
[f]_Marked as resolved_
[g]_Re-opened_
Ok @danny.djs.seo@gmail.com
[h]Here is source link incase u want to link to resource: https://www.energy.gov/sites/default/files/2021-08/bbrn-peer-cooling-081221.pdf
[i]I think i have cited the same @danny.djs.seo@gmail.com
