How to Install an Electric Water Heater

Installing a new electric water heater is a manageable DIY project if you have some plumbing and electrical experience. Whether you're upgrading for energy efficiency or replacing a worn-out unit, knowing the right steps will save you time and effort. This guide by The Trade Table walks you through installation, from removing the old unit to wiring the new one.

Before You Begin Installing

Check Local Codes & Choose the Right Heater

• Verify local plumbing codes to ensure compliance.
• Measure your space—newer models are often larger due to extra insulation.
• Consider a tankless water heater for on-demand hot water and energy savings.

Gather Your Tools & Materials

You’ll need:
✔ Adjustable pipe wrench
✔ Pipe cutter & fitting brush
✔ Non-contact voltage tester
✔ Screwdriver & wire cutter
✔ Soldering iron (if using copper pipes)

Materials:
✅ New electric water heater
✅ Copper or flexible water supply lines
✅ Thermal expansion tank (if required by code)
✅ Pipe adapters & plumber’s tape
✅ Water heater drain pan (recommended)

Step 1: Shut Off Power & Drain the Old Heater

1. Turn off power at the circuit breaker and confirm with a voltage tester.
2. Shut off the cold-water supply valve to the heater.
3. Drain the tank by attaching a garden hose to the drain valve and directing water to a safe location.
4. Disconnect electrical wires from the unit.

Step 2: Remove the Old Water Heater

• If your unit is heavy, use a hand truck and ask for assistance.
• If pipes are soldered, use a tubing cutter to detach them.
• Dispose of the old heater properly—check with your local sanitation service.

Step 3: Position the New Water Heater

• Place the new heater in a drain pan to catch potential leaks.
• Use shims to level the unit if needed.
• Ensure at least 6 inches of clearance around the unit for proper ventilation.

Step 4: Connect the Water Supply

1. Wrap heat trap fittings with Teflon tape and attach to the inlet & outlet.
2. Connect the cold-water supply line to the inlet (marked blue).
3. Attach the hot water line to the outlet (marked red).
4. If soldering pipes, do so before connecting to the heater to avoid damaging internal parts.

Step 5: Fill the Tank & Check for Leaks

1. Open the cold-water supply valve to fill the tank.
2. Turn on hot water faucets throughout your home to remove air from the system.
3. Check all connections for leaks—tighten if needed.

Step 6: Wire the Water Heater

Important: Do NOT connect power until the tank is full. Running dry will burn out heating elements.

1. Connect the ground wire to the grounding screw.
2. Match black & white wires to their corresponding terminals.
3. Secure connections and replace the electrical access panel.

Step 7: Set the Thermostat & Restore Power

• Adjust the thermostat to 120°F for safety and efficiency.
• Restore power at the breaker and test the unit.

Final Check & Maintenance Tips

✔ Allow the water to heat fully (about 1-2 hours) before testing hot water.
✔ Check for leaks at all connections.
✔ Flush the tank annually to remove sediment buildup

Upgrade Your Water Heater Today!

Need a new unit? The Trade Table offers a wide range of electric water heaters, expansion tanks, and installation supplies to get the job done right. Shop now!