Name: A.O. Smith Signature 500 40-Gallon Tall 6-year Warranty 50000-BTU Power Vent Natural Gas Water Heater
Brand: A.O. Smith
SKU: 1000213627
Price: 1299 USD
Availability: InStock
Rating: 4.4 (496 reviews)

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A. O. Smith's Signature 500 Series 40-Gallon Power Vented Water Heater is designed to provide efficient and reliable hot water for households with 3 to 4 people when sized appropriately. Featuring an environmentally friendly 50,000 BTU low NOx gas burner, this model delivers 87 gallons of hot water in the first hour utilizing an electronic gas valve for precise temperature control that requires no external power source. An LED status indicator on the valve enables easy diagnostics reporting and push-button ignition to simplify startup. Count on this 40-gallon natural gas water heater for safe operation thanks to a built-in system that reduces risks of accidental flammable vapor ignitions. A factory installed temperature and pressure relief valve and tamper-proof drain valve also mitigate hazards during use. Built to last, this model includes features Tank Guard® which is designed to provide ultimate tank protection and increase lifespan of the water heater. For added peace of mind, this unit includes a 6-year limited warranty. Want to save money on your energy bills? This unit operates at a 0.70 Uniform Energy Factor (UEF), which can reduce your energy consumption compared to less efficient models. Call 1-877-GOLowes to get this water heater installed.

Delivers the ideal amount of hot water for households with 3 to 4 people when sized appropriately
Features an environmentally friendly 50,000 BTU low NOx gas burner that delivers 87 gallons in the first hour
Electronic gas valve provides precise temperature control for optimum hot water delivery
Self-diagnostic electronic gas control incorporates an LED status indicator that monitors and reports on the system's operational status
Built-in safety system reduces the risk of accidental flammable vapor ignitions
Tall, slim 68.5-in H x 20-in diameter profile enables easier installation in narrow spaces
Flexible power vent installation through the wall or roof up to 180 feet
High-altitude-certified from 0 ft to 10,100 ft
Provides peace of mind with 6-year limited tank and parts and 1-year limited labor warranty

General
Type	Tank	Power Source	Gas
Fuel Type	Natural gas	Use Location	Indoor
Grade	Residential	Series Name	Signature 500
Ignition Type	Hot surface	Venting Type	Power
Vent Type	PVC/ABS/CPVC

Dimensions
Nominal Capacity (Gallons)	40	Weight (lbs.)	176
Rated Storage Capacity	38-Gallon	Width (Inches)	20
Vent Diameter(s)	2-in; 3-in; 4-in	Family Size	4
Depth (Inches)	20	Water Connection Size	3/4-in
Diameter (Inches)	20	Insulation Thickness (Inches)	2
Height (Inches)	68.5

Features
Point of Use	No	GPH Recovery at 90 Degrees F (Gallons)	56
Emission Rating	Low NOx	High Altitude Model	Yes
Annual Fuel Utilization Efficiency % (Percentage)	0	Installation Location	Closet
Uniform Energy Factor	0.70	Pilot Light Window	Yes
BTU Rating	50000	Pilot Reset Button	Yes
Super High Efficiency	No	Temperature and Pressure Relief Valve	Yes
Grid Capable	No	Water Connection Location	Top
Scale Prevention	No	Water Heater Style	Tall
Foam Insulation	Yes

Compatibility
For Use with RVs	No	Works with Android	No
Works with Apple HomeKit	No	Wi-Fi Compatibility	No
For Use with Mobile Homes	No	Works with the Google Assistant	No
Works with SmartThings	No	Bluetooth Compatibility	No
Works with Amazon Alexa	No	Smart Compatible	No
Works with iOS	No

Warranty
Warranty	6-year limited

Certifications
CA Residents: Prop 65 Warning(s)	Prop 65 WARNING(S) -	AHRI Certified	Yes
ENERGY STAR Certified	No	Safety Listing	UL safety listing

Miscellaneous
UNSPSC	40101800

Check out the Best Selling Water Heaters on Lowes.com

Review

4.4 out of 5

496 Reviews

91% Recommend this product

Ratings may include incentivized customer reviews.

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+ 18

What Customers Are Saying

The product has received mixed reviews. Many customers report positive experiences, highlighting the efficient performance and reliable hot water supply. However, a significant number of customers had negative experiences, with some receiving defective units that failed shortly after installation. There are concerns about the product's reliability and durability, as well as the manufacturer's responsiveness to issues. Customers should carefully consider these factors when deciding whether this water heater meets their needs.

Customer review summary generated by AI, including incentivized reviews.

496 Customer Reviews

Sort By

Easy install

Would Recommend

Like most water heaters, it was a bit awkward to lift, but installation was easy with a helper. It's providing plenty of hot water with no issues so far. I'm hoping for another 10 years of service, just like my last one.

JaybirdSeptember 5, 2026

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Two Water Heaters Failed in Less Than 6 years

Would Not Recommend

I am extremely disappointed with both the reliability of A. O. Smith water heaters and the customer service I received. My original A. O. Smith water heater failed after only about 4 years and was replaced under warranty. Now, the replacement unit has also failed and started leaking after less than 2 years of use. As a result, my family is currently without hot water at home. When I contacted A. O. Smith, I was told that the replacement unit does not receive a new warranty and is only covered ...

JeffAugust 24, 2026

https://photos-us.bazaarvoice.com/photo/2/cGhvdG86bG93ZXM/38fc6648-07fd-5a43-a756-1628a6d8b4da

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Response from Published by the A. O. Smith Team

We are sorry to hear of your experience. We want to ensure the issue is resolved.

Please send your phone number to talktous@aosmith.co...

Published by the A. O. Smith TeamAugust 26, 2026

Missing Manufacturer Tag

Would Not Recommend

HOW IS IT POSSIBLE THAT THE MANUFACTURER TAG IS MISSING!!! This should be a massive fine to the company for lack of quality control. I only noticed after I already installed it and filled it up. This is UNACCEPTABLE! Along with that, the water heater is dented, scratched, why does it look like a return??

DIYguyAugust 20, 2026
From Signature 500 50-Gallon Tall 6-year Warranty 50000-BTU Power Vent Natural Gas Water Heater

https://photos-us.bazaarvoice.com/photo/2/cGhvdG86bG93ZXM/2bf808b2-0fa1-5229-8685-1fff35efa85e

https://photos-us.bazaarvoice.com/photo/2/cGhvdG86bG93ZXM/cf03dc11-ed38-5826-bffd-640ddbfb0c54

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Response from Published by the A. O. Smith Team

We are sorry to hear of your experience.

We recommend reaching out to Lowe's Customer Care at 1-800-445-6937 or Text 84109.

Published by the A. O. Smith TeamAugust 27, 2026

Awesome purchase

Would Recommend

I bought this and it had a dent so I went into store and charrisa in customer service took care of me. I walked out a satisfied. She was awesome and deserves lunch bought from a boss!! I did finally get the water heater installed and what a difference. Love the purchase I made!!

Happy customerAugust 2, 2026
From Signature 500 50-Gallon Tall 6-year Warranty 50000-BTU Power Vent Natural Gas Water Heater Verified Purchaser

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Great upgrade from out previous one that we had

Would Recommend

I am not really sure how it is as I have only had it for 1 day. I am glad that we have hot water now. Easy installation.

ReginaJuly 20, 2026

From aosmith.com

Aode Rod Check Needed

Would Recommend

I was surprised to read in the owner's manual that because I have soft water I need to check the anode rod yearly for end-of-life disintegration! I didn't know soft water was more corrosive than hard water! I wonder if that is what destroyed my old one after only 5 years of service.

FredJuly 1, 2026

From aosmith.com

Defective product and terrible customer service

Would Not Recommend

I found a similar story on this site, so this appears to be a systemic problem. I purchased an AO Smith water heater from Lowe's in 2025 along with their installation service. The installation was significantly overpriced, but it was completed quickly, and I was in a hurry. After the water heater was installed, however, the water temperature was far too hot. I spent a great deal of time calling Lowe's customer support before I was finally able to get the installer to return. Unfortunately, he si...

DennisJune 25, 2026

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Response from Published by the A. O. Smith Team

We are sorry to hear of your experience.

We recommend reaching out to Lowe's Customer Care at 1-800-445-6937 or Text 84109.

Published by the A. O. Smith TeamJune 30, 2026

Good water heater with reliable supply of hot wate

Would Recommend

It is a 20” heater, however the air intake on the back requires the heater to be mounted several inches from the back wall. If you put it in a tight spot, you’d better take it into account.

AssolJune 9, 2026
Verified Purchaser

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