Many homeowners have experienced the momentary dimming or pulsing of lights when their air conditioning unit kicks on. In more extreme cases, you may notice a dimming of your lights for the duration your AC is on. This common occurrence may seem harmless but can indicate deeper issues within your home’s electrical system.
Do you think your lights are flickering for other reasons? Read our blog for more information on why this might be happening.
Electrical Demand Surge
When your air conditioning system starts, it requires substantial electricity to power its compressor. This sudden surge in demand can temporarily reduce the power available for other devices in your home, causing your lights to dim or flicker.
You may be more likely to experience this if your home’s electrical infrastructure is not adequately equipped to handle such a demand. Similarly, you may also notice this during prolonged heatwaves, when there is greater demand on the power grid.
Voltage Drops
The electrical surge when the AC unit begins its cycle can lead to a temporary voltage drop elsewhere in your home. This drop affects the performance of all electrical appliances in the home, but it’s often most noticeable with your lighting. Consistent or severe voltage drops can cause damage to electrical devices over time, making it essential to identify and address the root cause.
Older or Undersized Wiring
Though dimming lights when your HVAC system kicks on can happen in any home, it is more common in older homes or those with outdated wiring or overburdened circuits. In these situations, the electrical system may struggle to cope with the sudden power demands of modern AC units, especially when other appliances are running. This can result in overloaded circuits, leading to dimming lights or even more severe electrical issues.
Read our blog to learn about electrical panel upgrades and how to know if your system needs one.
How to Troubleshoot Dimming Lights
Check for Other Symptoms
If your lights dim when the AC starts, pay attention to other symptoms as well. Do the lights flicker or dim for more than a few seconds? Are there power surges when multiple appliances are running at once? Do you notice this issue more at specific times of day, or is it consistent?
Test Other Appliances
Determine if the dimming occurs when other high-demand appliances, like microwaves, washers, or dryers, are also turned on. Similarly, does this only happen when all of your lighting is on, for example, at night when your lighting demands are greater? If dimming occurs persistently, your home’s electrical capacity might be insufficient for your needs.
Inspect Your Electrical System
Check your electrical system for any tripped circuit breakers or other warning signs of electrical problems, such as warm outlets or burning smells. Look for these signs both when your HVAC system is running and when it is off. Seeing these issues could indicate an overloaded system or faulty wiring that needs professional attention.
Consider HVAC Age and Size
An older or improperly sized air conditioning unit can place excessive strain on your electrical system. If dimming lights are an ongoing issue, it may be beneficial to have your HVAC system evaluated to ensure it is suited for your home's electrical capacity and needs.
Reach Out to Valley for Help: Expertise in HVAC and Electrical Systems
Valley Heating, Cooling, Electrical and Solar employs experienced, certified HVAC technicians and licensed electricians, uniquely qualifying us to handle both the mechanical and electrical components of your problem. If you are experiencing issues with dimming lights or other problems when your HVAC system is running, our team can assess whether the issue lies with your AC unit or your home’s wiring system.
Remember, attempting DIY fixes for electrical issues can be dangerous and may exacerbate the problem. Our team provides safe, long-lasting solutions without causing further electrical complications.
Don’t wait for the problem to worsen—reach out to Valley, your trusted San Jose HVAC and electrical specialists.