Name: A.O. Smith Signature 100 40-Gallon Tall 6-year Warranty 36000-BTU Liquid Propane Water Heater
Brand: A.O. Smith
SKU: 1002550506
Price: 859 USD
Availability: InStock
Rating: 4.2 (219 reviews)

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A. O. Smith's 40-gallon propane water heater provides efficient and reliable hot water for households with 2 to 3 people when sized appropriately. With an environmentally friendly 36,000 BTU gas burner, this propane tank water heater delivers 80 gallons of hot water in the first hour. It features an electronic gas valve that provides precise temperature control for optimum hot water delivery without the need for an external power source. For your convenience, the gas valve also includes an LED status indicator for diagnostics reporting and a push button ignition to simplify the startup process. This liquid propane water heater is designed with your safety in mind. With a built-in safety system, this model reduces the risk of accidental flammable vapor ignitions. A factory-installed temperature and pressure relief valve and tamper-proof drain valve also ensure safe operation. This model is built to last. It features Tank Guard® which is designed to provide ultimate tank protection and increase lifespan of the water heater. This added protection comes with a 6-year limited warranty to give you additional peace of mind. 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 36,000 BTU ultra-low NOx burner that delivers 80 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 61.75-in H x 20-in diameter profile enables easier installation in narrow spaces
Tank Guard® provides advanced tank protection that extends the life of your gas water heater
High-altitude certified from 0 ft to 10,100 ft
Provides peace of mind with a 6-year limited tank and parts guarantee and a 1-year limited labor warranty

General
Type	Tank	Power Source	Gas
Fuel Type	Liquid propane	Use Location	Indoor
Grade	Residential	Series Name	Signature 100
Ignition Type	Piezo	Venting Type	Atmospheric
Vent Type	Type B double wall

Dimensions
Nominal Capacity (Gallons)	40	Weight (lbs.)	135.75
Rated Storage Capacity	38-Gallon	Width (Inches)	19.75
Vent Diameter(s)	3-in; 4-in	Family Size	4
Depth (Inches)	19.75	Water Connection Size	3/4-in
Diameter (Inches)	20	Insulation Thickness (Inches)	2
Height (Inches)	61.75

Features
Point of Use	No	GPH Recovery at 90 Degrees F (Gallons)	42
Emission Rating	Ultra Low NOx	High Altitude Model	Yes
Annual Fuel Utilization Efficiency % (Percentage)	0	Pilot Light Window	Yes
Uniform Energy Factor	.64	Pilot Reset Button	Yes
BTU Rating	36000	Temperature and Pressure Relief Valve	Yes
Super High Efficiency	No	Water Connection Location	Top
Grid Capable	No	Water Heater Style	Tall
Scale Prevention	No	Leak Detection	No
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	CSA safety listing

Miscellaneous
UNSPSC	40101800

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Review

4.2 out of 5

219 Reviews

84% Recommend this product

Ratings may include incentivized customer reviews.

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+ 8

What Customers Are Saying

Customers overwhelmingly praise this water heater for reliable hot water delivery, fast recovery in as little as 45 minutes, and straightforward installation. Many highlight consistent performance through back-to-back showers, quiet operation, and durable construction, with several referencing previous units lasting 22 to 25 years. The compact design and energy efficiency receive strong approval. A small group reports pressure relief valve leaks and occasional burner noise, while a few mention difficulty accessing qualified service technicians. Overall, most customers consider it a dependable, well-built investment.

Customer review summary generated by AI, including incentivized reviews.

219 Customer Reviews

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Ease of installation.

Lee AJuly 20, 2026
Verified Purchaser

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Propane water heater

The propane water heater works well. Easy to install. Only problem is it costs $200 more than natural gas. What a rip off from the propane association.

July 20, 2026
Verified Purchaser

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New tank with a broken pressure relief valve

After installing the hot water tank, water kept coming out of the pressure relief valve. We had to go to a hardware store to purchase a new pressure relief valve and replace it. Major inconvenience and had to spend more money. Works great now.

ChristinaJuly 9, 2026
From Signature 100 50-Gallon Tall 6-year Warranty 37000-BTU Liquid Propane Water Heater Verified Purchaser

https://photos-us.bazaarvoice.com/photo/2/cGhvdG86bG93ZXM/be4a3ab5-7c92-5caf-bad6-69059cdebd1e

https://photos-us.bazaarvoice.com/photo/2/cGhvdG86bG93ZXM/6eb4ac30-e874-5b28-9af9-e58559c3105f

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Easy Peazy Pick-up

Would Recommend

I asked for a little Associate assistance with the transaction and "Boom". An exceptionally talented Associate jumped right in and walked me through the process of picking up my Gas Hot Water Heater. They even loaded it for me in my truck. I was then on my way. Could not have been more pleased with the process. Oh!, P.S. I got a Pro to install for me. Took about an hour. Minimum cost.

NoHotWaterJune 30, 2026
From Signature 100 50-Gallon Tall 6-year Warranty 37000-BTU Liquid Propane Water Heater Verified Purchaser

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Service

Would Recommend

Very good product

Co51June 22, 2026
Verified Purchaser

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Your going to need help unloading it

Would Recommend

It was exactly what I need

Service was amazingMay 22, 2026
Verified Purchaser

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39 Questions

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		Ratings	219
		Fuel Type	Liquid propane
		Type	Tank
		Height (Inches)	61.75
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