Is the ENT-40 110 a good choice for your replacement?
The A.O. Smith ENT-40 110 is a tall electric storage water heater in the ProLine series. Its narrower 18-inch diameter may be useful when floor space is limited, but the taller tank still needs room for top water connections, electrical access and service. Water Heating Experts reviews the existing installation and your household’s hot-water needs before recommending equipment in Palm Beach Gardens, Jupiter or nearby communities.
A.O. Smith lists a 40-gallon nominal capacity, 36 gallons of rated storage and a 53-gallon first-hour rating. The first-hour rating is a standardized delivery measurement, not a claim that the tank physically contains 53 gallons. If your household regularly runs out of hot water during back-to-back showers, we check both recovery and how much hot water is used at once rather than relying on the gallon label alone.
Dimensions and choosing between tall, short and lowboy tanks
The ENT-40 110 stands 61¼ inches high and measures 18 inches in diameter, with ¾-inch top-mounted water connections. The tank dimensions do not include additional clearance for piping, fittings, a water shutoff, removal and service access. We also check drainage, the temperature-and-pressure relief discharge and any other work required at the location.
The A.O. Smith ENS-40 110 short electric model is approximately 49¾ inches high by 20½ inches wide, with 37 gallons rated storage and a 55-gallon first-hour rating. If height is especially tight, compare the ENLB-40 110 lowboy at 32 inches high by 23 inches wide. These are distinct water heaters, and a shorter unit may be more suitable even when all three are in or near the same nominal capacity class. We select for available space and performance, not just advertised gallons.
Electrical requirements and hot-water recovery
In its standard configuration, the ENT-40 110 uses 240-volt electric service with two 4,500-watt heating elements. A.O. Smith lists a maximum input of 4,500 watts for the standard non-simultaneous arrangement, not 9,000 watts. Its published recovery rate is approximately 21 gallons per hour at a 90°F temperature rise. A correct replacement requires checking the supplied unit’s data plate, the existing electrical circuit, breaker and wiring, and any necessary plumbing changes.
The manufacturer’s technical specifications give this model a 0.92 Uniform Energy Factor (UEF). This is an electric resistance storage water heater, not a heat-pump model. If reducing energy use is a primary goal, WHE can help determine whether the installation conditions make a hybrid heat-pump water heater worth comparing.
Tank protection, warranty and maintenance
A.O. Smith lists a Blue Diamond glass tank lining, a CoreGard anode rod with a stainless-steel core, a DynaClean diffuser, a lower Incoloy heating element, and a brass drain valve. These features are intended to help protect the tank but are not a substitute for suitable water conditions or manufacturer-recommended maintenance.
The listed warranty is six years limited coverage for the tank and parts, subject to the manufacturer’s written conditions. Labor and the cost of removing or installing equipment are separate. WHE confirms the exact model’s availability, replacement scope and applicable installation coverage when preparing your free estimate.
ENT-40 110 frequently asked questions
Does the ENT-40 110 actually store 40 gallons?
A.O. Smith lists 40 gallons nominal capacity and 36 gallons rated storage. The 53-gallon first-hour rating is a separate measure of hot-water delivery under standard test conditions.
How much room does the tall ENT-40 110 need?
The tank measures 61¼ inches tall and 18 inches in diameter. Additional space is needed for top-mounted water connections, electrical access and servicing. WHE checks the complete installation space before recommending it.
What is the difference between ENT-40 110 and ENS-40 110?
ENT-40 110 is taller and narrower, at 61¼ by 18 inches, with 36 gallons of rated storage and a 53-gallon first-hour rating. The short ENS-40 110 is 49¾ by 20½ inches, with 37 gallons rated storage and a 55-gallon first-hour rating. WHE compares the actual space and hot-water use.
What electrical supply does this water heater use?
The standard model uses 240 volts and two 4,500-watt elements with a maximum connected input of 4,500 watts in non-simultaneous operation. The exact heater nameplate and existing electrical installation must be checked before replacement.
Can I request this model for installation in Palm Beach Gardens or Jupiter?
Yes, WHE serves Palm Beach Gardens, Jupiter and surrounding Palm Beach County communities. Mention the ENT-40 110 in your free estimate request. We will confirm your location, equipment suitability, current availability and installation requirements.
Get help selecting your replacement
To help us assess your installation, text a photo of the current heater’s model label and a second photo showing its surrounding space and piping. WHE can compare this model with other A.O. Smith water heater installation options and recommend a practical next step.
Technical references: A.O. Smith ENT-40 110 official product page, A.O. Smith ProLine Standard Electric specification sheet, installation and use guide and residential limited warranty. Specifications verified October 2026. The product page’s promotional paragraph differs from its technical specifications on UEF; this guide follows the technical table and specification sheet at 0.92. Verify the supplied unit before installation.