Electric water heaters are one of the largest single electrical loads in most Aiken homes, drawing between 4,500 and 5,500 watts on a standard tank unit and up to 36,000 watts on a whole-home tankless system. This level of power demand requires a dedicated 240-volt circuit with properly sized wire, a correctly rated breaker, and a code-compliant disconnect switch. Getting any of these wrong creates a serious fire or shock hazard.
Whether you are replacing an aging tank water heater, upgrading from gas to electric, or installing a new tankless unit, the electrical wiring must be done right. Many older homes in Aiken, Graniteville, and Jackson have electrical panels and wiring that were not designed for today's water heater demands. Unity Power & Light handles the complete electrical side of water heater installation -- from panel capacity evaluation through final inspection -- ensuring your new water heater has the safe, reliable power supply it needs.
What We Do
We handle all electrical work associated with water heater installation, from running new circuits to connecting the unit and installing required safety devices.
Dedicated 240V Circuit
A new 240-volt circuit from your electrical panel to the water heater location, sized correctly for your specific unit. Standard tank heaters typically require a 30-amp circuit with 10-gauge wire. We verify your panel has capacity and install the correct breaker.
Wire Sizing & Routing
Proper wire gauge is critical for safety and code compliance. Undersized wire overheats under load and creates a fire hazard. We calculate the exact wire size based on your water heater's amperage draw, circuit length, and NEC requirements.
Disconnect Switch Installation
South Carolina code requires a disconnect switch within sight of the water heater so it can be safely de-energized during maintenance or emergencies. We install a properly rated disconnect in the correct location as part of every water heater wiring job.
Tank Water Heater Wiring
Standard tank water heaters (40-80 gallon) use 4,500 to 5,500 watt heating elements operating on 240 volts. We connect the wiring to the unit's junction box with proper strain relief, wire nuts, and grounding per manufacturer specifications.
Tankless Water Heater Wiring
Electric tankless units require substantially more power -- often two or three 40-amp circuits with 8-gauge or 6-gauge wire. We evaluate your panel capacity, run multiple dedicated circuits if needed, and coordinate breaker placement to balance the load across panel phases.
Panel Upgrades for Water Heaters
If your electrical panel lacks capacity for a new water heater circuit, we can upgrade your panel as part of the project. Many older Aiken homes have 100-amp panels that cannot support a tankless unit without an upgrade to 200 amps.
Our Installation Process
Evaluate Panel Capacity and Existing Wiring
We inspect your electrical panel to confirm it has available space and amperage capacity for the new water heater circuit. For tankless installations requiring multiple high-amperage circuits, we calculate total household load to determine whether a panel upgrade is necessary before proceeding.
Run Dedicated Circuit
We run properly sized cable from your electrical panel to the water heater location. The wire gauge, breaker size, and cable type are matched to your specific water heater model. We route cable through walls, attics, or crawlspaces and protect exposed runs with conduit as required by code.
Install Disconnect and Connect Unit
We install the code-required disconnect switch within sight of the water heater, then connect the wiring to the unit's junction box. All connections are made with proper strain relief fittings, wire connectors, and grounding per the manufacturer's installation instructions and NEC requirements.
Test and Verify Safe Operation
We energize the circuit, verify correct voltage at the water heater, test the disconnect switch, confirm the breaker is properly sized and labeled, and check all connections for tightness. We verify the water heater is heating correctly before leaving and clean up all installation materials.
Why Professional Installation Matters
Water heater wiring is high-amperage 240-volt work. Mistakes in circuit sizing, wire gauge, or connections create real dangers -- not just code violations.
Correct Wire Sizing
A standard 4,500-watt tank water heater draws about 18.75 amps on a 240-volt circuit. NEC requires 10-gauge wire and a 30-amp breaker for this load. A tankless unit drawing 120 amps needs multiple circuits with 6-gauge wire and 40-amp breakers. Using undersized wire is one of the most common and dangerous DIY mistakes -- the wire overheats under load, melting insulation and starting fires inside walls.
Disconnect Switch Requirements
South Carolina electrical code requires a disconnect means within sight of any water heater for safe maintenance and emergency shutdown. This is not optional. Many homeowners and handymen skip this requirement, leaving no safe way to de-energize the unit without walking to the breaker panel. We install the correct disconnect type and rating as part of every installation.
Panel Load Balancing
A 240-volt water heater circuit uses two breaker slots and draws from both legs of your electrical panel. Tankless units requiring multiple 240V circuits can significantly unbalance your panel if breakers are placed incorrectly. We calculate and balance the load across both panel phases to prevent overloading either leg.
Tankless Electrical Demands
Many homeowners switch to tankless units expecting lower utility bills but are surprised by the electrical requirements. A whole-home electric tankless unit can require 150 amps of circuit capacity -- more than half of a standard 200-amp panel. We evaluate whether your panel can support a tankless unit before you invest, and we are honest about when a panel upgrade is necessary.
Electric Water Heater Wiring Pricing
Unity Power & Light provides flat-rate pricing for water heater electrical work. You will know the exact cost before we begin -- no hourly billing and no surprise charges.
Final pricing depends on the distance from your panel to the water heater, the wire gauge required, whether your panel needs additional breaker space, and the specific requirements of your water heater model. We provide an exact quote after evaluating your home.
For a detailed comparison of electric and gas water heater options for Aiken homes, read our blog post: Electric vs. Gas Water Heaters: What Aiken Homeowners Should Know
Why Choose Unity Power & Light
Need other electrical work done at the same time? We offer a full range of residential electrical services including panel upgrades, outlet installation, and more. Combining projects in a single visit saves you time and money.
Need Electric Water Heater Wiring?
Serving Aiken, SC and surrounding communities including North Augusta, Graniteville, New Ellenton, Jackson, and Clearwater. Get your flat-rate quote today.