Why Lights Dim When the Central AC Unit Starts
Why do my lights dim when my central AC Unit comes on? Evaluating an Older Home Electrical System.
- It’s an older home and most outlets are 2 prong.
- There is no ground wire.
- The old electrical wiring is 2 strand black and white wires.
This home electrical question came from: Phillip, a Handyman from Texarkana, Texas.
Additional Comments: Very good. Lots of information.
Thanks for your electrical wiring question Phillip.
Evaluating an Older Home Electrical System
Application: Upgrading an Older Home Electrical System.
Skill Level: Advanced – Best performed by a Licensed Electrician.
Tools Required: Electricians Tools including a pouch of hand tools and the various power tools necessary for installing electrical circuit wiring and upgrading the electrical panel as required.
Estimated Time: Depends on type of existing panel or fuse box, the replacement panel to be installed, the original wiring methods that were used for installing the existing wiring, the number of circuits to be replaced or new circuits to be installed, the and available access to the project areas.
Precaution: This is an extensive project that should be performed by a Licensed Electrician and typically requires specifications in accordance with the local building department and the utility company or electric service provider. Working in an electric panel is dangerous due to arc flash hazards and the possibility of electric shock.
Notice: Making changes to home electrical wiring and the electric service panel should be done according to local and national electrical codes with a permit and be inspected.
Dim Lights when Large Electrical Equipment is Starting
- Air conditioners and central units consume high quantities of electrical current especially when they first start.
- Depending on the size of the electrical service panel and the quality of electrical power from the local electric utility company the lights in the home may dim when the air conditioner first starts.
- You have stated that a ground wire is not present so you may want to have the electrical service evaluated and get an estimate to upgrade the main electrical service panel.
- Upgrading the home electrical service panel will supply more circuit capacity for the home.
- Installing additional circuits as needed will reduce existing circuit overloaded circuits.
- Have the home electrical system evaluated for more specific suggested improvements.
More about Upgrading Home Electrical Wiring
Electrical outlet wiring
Wiring Electrical Outlet for the Home
Home electrical wiring includes 110 volt outlets and 220 volt outlets and receptacles which are common place in every home. See how wiring electrical outlets for the home are done.
Electrical Wire for the Home
Complete listing of electrical wire types and parts used for home projects with electrical code information serves as selection guidelines.
For more information about Grounding
Electrical Grounding Methods and Requirements
Listing of electrical codes for grounding with examples of electrical grounding codes for home electrical wiring.