Upgrading Your Electrical Panel: A Step-by-Step Guide to Replacing a Challenger Panel

Updated at: 25/05/2025

Outdated electrical panels, like the often-encountered Challenger panel, pose a significant safety risk and can limit the power available to your home. A Challenger panel, while functional in its time, may not meet modern safety standards or accommodate the increased energy demands of today's appliances and technology. Its age alone could lead to overheating, sparking, and even fire hazards, making an upgrade a crucial investment in both your home's safety and functionality. Failing to address these issues could result in costly repairs or worse.

This lack of capacity is often felt as insufficient power outlets or tripping breakers. This step-by-step guide will walk you through the process of safely and effectively replacing your outdated Challenger panel with a modern, code-compliant upgrade, ensuring your home's electrical system is safe, efficient, and ready for the future.

Preparation and Safety Guidelines

Tools Needed
  • Screwdrivers
  • Allen keys
  • Wire strippers
  • Penetrox
  • Electrical tape
  • New Square D Panel
  • Connectors
  • Lock nuts
Safety Guidelines
  • **Always turn off the main power breaker before starting any work.** Failure to do so can result in serious injury or death from electric shock.
  • **Never work on electrical panels alone.** Have a qualified electrician assist you or supervise your work if you lack experience. Electrical work is inherently dangerous.
  • **Verify the power is off before touching any wires or components.** Use a non-contact voltage tester to confirm the power is completely disconnected at the panel and the service entrance.

Step-by-Step Instructions

  1. Preparation and Disconnection

    • Label every single wire.
    • Turn off each individual breaker and the main breaker.
    • Remove all hot wires, then neutrals and grounds, followed by lock nuts.
    • Remove main feeders from the main breaker using Allen keys.
    Remove main feeders from the main breaker using Allen keys.Remove main feeders from the main breaker using Allen keys.Remove main feeders from the main breaker using Allen keys.
    Preparation and Disconnection
    • Remove the panel from the enclosure.
    Remove the panel from the enclosure.
    Preparation and Disconnection

  2. Panel Installation

    • Mount the new Square D panel.
    Mount the new Square D panel.
    Panel Installation

  3. Wire Management and Connection

    • Install wires using the quick lock system where applicable, and connectors/lock nuts for larger gauge wires.
    • Separate and straighten all wires neatly.
    • Extend wires if necessary to reach bus bars.
    • Install main service feeders.
    Install main service feeders.Install main service feeders.
    Wire Management and Connection
    • Install breakers and connect branch circuit conductors.
    Install breakers and connect branch circuit conductors.
    Wire Management and Connection

  4. Testing and Completion

    • Reinstall service outlet(s).
    • Test all circuits and ensure proper functionality.
    Test all circuits and ensure proper functionality.Test all circuits and ensure proper functionality.
    Testing and Completion

Read more: Installing an Outdoor GFCI Receptacle: A Step-by-Step Guide

Tips

  • Use penetrox to make wire removal easier.
  • Be careful with old wiring to avoid nicking or damaging it.
  • Straighten wires as you remove them for easier reinstallation.
  • Leave extra slack on service conductors for future maintenance.
  • Use the quick lock system for efficient wire connection whenever possible.

Common Mistakes to Avoid

1. Incorrect Wire Sizing

Reason: Using wires that are too small for the amperage of the circuit leads to overheating and potential fire hazards.
Solution: Always use wire sized appropriately for the circuit's amperage, as specified by the National Electrical Code (NEC).

2. Neglecting Proper Grounding

Reason: Improper grounding can lead to electrical shocks and damage to appliances.
Solution: Ensure all grounding wires are properly connected and that the ground bar is securely fastened within the electrical panel.

FAQs

Do I need a permit to replace my electrical panel?
Yes, almost always. Electrical work is heavily regulated for safety reasons. You'll need to obtain the necessary permits from your local building authority before starting the project. Failing to do so can result in fines or even invalidate your homeowner's insurance.
How much does it cost to replace an electrical panel?
The cost varies greatly depending on factors like the size of the new panel, the complexity of the installation (e.g., needing to run new wiring), your location, and the electrician's rates. Expect to pay anywhere from $1000 to $5000 or more. Getting multiple quotes from licensed electricians is highly recommended.