A.O. Smith Signature 100 40-Gallon Tall 4500-Watt Double Element Electric Water Heater -Item #816154 | Model #E6-40H45DV

• Ideal hot water delivery for households with 2-3 people when sized appropriately

• Two 4,500-watt copper heating elements provide a first hour delivery of 53 gallons

• Save money and energy with this energy efficient model that operates at a 0.92 Uniform Energy Factor (UEF)

• Tall and slim 61.25-in H x 18-in diameter profile is designed for easier installation

• Premium heating elements, anode rod and fused ceramic tank shield provide superior tank protection and extend water heater life

• Non-CFC polyurethane foam insulation and factory-installed heat trap nipples reduce heat loss for maximum efficiency and energy savings

• Easy temperature control with adjustable thermostat can be set higher for dishwashers and laundry machines or lower as needed

• Factory-installed temperature and pressure relief valve and tamper-proof drain valve ensures safe operation
  

Specifications

What our Experts Think

• Reliable hot water for small households: The 40-gallon capacity with dual 4500-watt copper heating elements delivers a first-hour rating of about 53 gallons, providing consistent hot water for homes with 2–3 people.

• Efficient everyday performance: With a 0.92 Uniform Energy Factor (UEF), this electric water heater offers dependable heating while helping reduce energy costs compared with older or less efficient models.

• Tall design for easier installation: The slim tall profile (about 61.25 in. high and 18 in. diameter) is ideal for installation in utility rooms or tight spaces where floor area is limited but vertical space is available.

• Durable tank construction: Features premium copper heating elements, a protective anode rod, and a fused ceramic tank shield, helping protect against corrosion and extend the life of the water heater.

• Improved insulation for energy savings: Non-CFC polyurethane foam insulation combined with factory-installed heat trap nipples helps reduce standby heat loss and maintain water temperature efficiently.

• Simple temperature control: An adjustable thermostat allows homeowners to easily set the water temperature based on household needs such as showers, laundry, or dishwashing.

• Safety-focused design: Includes a factory-installed temperature and pressure relief valve and tamper-resistant drain valve to help ensure safe and reliable operation.

• Dependable warranty coverage: Backed by a 6-year limited tank and parts warranty, offering solid protection and long-term peace of mind.

Q&A

Q: What household size is this 40-gallon water heater best for?
A: The 40-gallon capacity is ideal for households of 2–3 people, providing reliable hot water for showers, laundry, and daily household needs.

Q: How powerful are the heating elements?
A: This model features two 4,500-watt copper heating elements that deliver fast heating and a first-hour hot water delivery of about 53 gallons.

Q: Is the water heater energy efficient?
A: Yes. It operates with a Uniform Energy Factor (UEF) of around 0.90–0.92, helping reduce standby heat loss and energy consumption.

Q: What are the dimensions of this tall water heater?
A: The unit has a tall, slim profile measuring about 61.25 inches high and 18 inches in diameter, making it suitable for narrow installation spaces.

Q: What features help extend the tank’s lifespan?
A: The heater includes a fused ceramic tank shield, protective anode rod, and premium heating elements designed to reduce corrosion and extend tank life.

Q: What safety features are included?
A: It includes a factory-installed temperature and pressure relief valve, adjustable thermostat, and tamper-resistant drain valve for safe operation.

Q: What are the installation requirements?
A: This electric water heater runs on 240 volts, has top water connections, and is designed for indoor residential installation.

Maintenance Tips

• Flush the tank yearly: Drain and flush the tank every 6–12 months to remove sediment buildup that can reduce heating efficiency and shorten the life of the heating elements.

• Inspect the anode rod: Check the sacrificial anode rod annually and replace it if heavily corroded to help prevent internal tank rust and extend water heater lifespan.

• Check heating elements and thermostat: Periodically inspect the upper and lower 4500-watt heating elements and thermostats to ensure consistent hot water and efficient operation.

• Test the T&P relief valve: Lift and release the temperature & pressure relief valve once a year to confirm it opens properly and prevents excess pressure buildup.

• Look for leaks and corrosion: Regularly inspect water connections, valves, and the base of the heater for moisture, rust, or leaks.

• Keep the unit area clean: Maintain a dry, clear space around the water heater to allow proper airflow and easier maintenance access.

• Fill the tank before powering on: Always ensure the tank is completely filled with water before turning on power to prevent dry-firing and element damage.