40 Gallon Tall Natural Gas Water Heater - 12 Year Warranty

40 Gallon Tall Natural Gas Water Heater - 12 Year Warranty

Model: N40T121-403    Lowe's Item* #: 333564


  • FLAME LOCK® Safety System Reduces the Risk of Accidental Fires Involving Flammable Vapors
  • Electronic Gas Valve has fewer moving parts than a conventional mechanical gas valve, for durability and long life-no external power source is needed
  • Self-Diagnostic Electronic Gas Control incorporates an LED status indicator that monitors and reports on system operational status
  • Piezo Electric Igniter makes lighting the pilot fast and easy
  • Environmentally friendly polyurethane foam insulation reduces heat loss for maximum efficiency, saves money
  • Ceramic tank lining and aluminum anode rod protects tank from corrosion, for long tank life
  • Factory installed temperature and pressure relief valve ensures safe operation

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Product Dimensions
Height w/Draft Hood:62.00"
Weight:127 lbs.
Vent Type:Type B Double Wall
Vent Diameter:3"
Configuration and Overview
Capacity:40 Gallons
Family Size:4
Energy Star Certified:No
Energy Factor:0.59
Annual Cost of Operations:$277
LCD Display:No
Self Cleaning:Yes
Warranty Tank:12 Years
Warranty Parts:12 Years
Warranty Labor:1 Year
BTU Input:40,000 BTUs
Emissions Standards:Low NOx
Ignition Type:Pilot with Piezo Igniter
Foam Insulation:1 inch
Water Connection Location:Top
Water Connection Size:3/4 inch
T&P Relief Valve:Yes
Energy & Eco-Friendly
Energy Factor:0.59
40 Gallon Natural Gas Water Heater - N40T121-403 4.5 5 174 174
Hottest water so far! Wow! What a difference in the amount of hot water! Out unit is set only at hot and it cranks out more hot water than our 16 year old heater ever did! I did not rate the quality yet is it was just installed, but it seems like a well built unit. Like the darker color gray vs the white color. My friend just bought a 50 gallon 6year Whirlpool hot water heater, but I decided to go for the 40 gallon but with a 12 year warranty for the piece of mind, especially with the new sensors up front. We'll see if it lasts that long! July 14, 2011
This product is very loud The heater was just installed. Easy installation. Heated water in about 1 hour. Very noisy February 15, 2015
This product was taller than the product description online by 4 inches, causing purchase of different fittings. This product said it was 58 inches tall in the online description and came in as 62 inches tall causing me to have to purchase two 18 inch flexible copper connections to make the installation work. I had purchased based on the product height to replace with the same plumbing set up. The box did say 62 inches when it arrived, just the online description was incorrect. February 11, 2015
Installation was easy; just needed new nipples Page 22 of the manual reads "The Gas Water Heater Hook-up KIT" under step 11...another shopping trip was required to purchase nipples. We purchased nipples with heat traps. The nipples on the old heater didn't appear to have ever had heat traps and nipples were the only NEW hook-up connections that we had to purchase for this install--easier to make the shopping trip compared to removing the old ones from the old heater. February 3, 2015
Excellent easy to use, easy to installing, light weight. the instruction is very clearly. The price is good. January 28, 2015
This water heater was easy to install. This water heater was easy to install. and instruction how to star for the first time was very user friendly. It is also coming with 12 years warranty for parts and inner tank. January 18, 2015
Product seems well built and easy to use. I've never bought a whirlpool water heater before. I purchased 2 (same model N40T121-403 Natural gas with 12 year tank warranty) in the last 4 months to put in rentals. Why would I buy one of the more expensive products for a rental? Because the extra money is worth it IF the quality and durability is there. I believe those characteristics may be in this water heater based on the fact that I have other whirlpool appliances (in my own house) and I find them durable, easy to use and have the appropriate amount of features. I'm hoping the same applies to their water heaters. The NT40T121 is definitely easy to install. I wouldn't say that I'd recommend this one because of the ease of install, just that it was easy. Most water heaters are similar in regards to the parts that require "installation" so I wouldn't expect this one to be difficult. (i.e. it's not the water heaters fault the space where it's located is too small to work in, you kinked your copper flex, bought the wrong couplings or didn't measure the gas valve connection height before buying so the hard gas lines don't match up requiring you to buy yet another flex line). I do think the gas valve on these models, having the enclosed ignitor, easy to read information and diagnostic LED is great. I specifically say this because it makes it easy to troubleshoot for people who are "less than familiar" with water heaters. Just like a furnace..2 blinks means this problem, 3 blinks means that problem! Nothing is worse than getting a call at some random hour from someone complaining that the water heater isn't working and they don't know why nor can they fix it. In case the end user can't read and/or understand the diagnostic system itself, having the help of the diagnostic LED makes remote troubleshooting a much easier and possibly time/frustration saving event. The one thing I don't like about this model is the dust guard that goes around the bottom. It wraps around the outside circumference on the bottom of the tank and sits flush with the floor. It helps keep the air intake clean of debris. Instructions state that it should be cleaned often. This is a water heater....no one remembers, nor wants, to clean a dust guard, especially if removing the dust guard is difficult due to clearances. If this were in an unused part of the house it might not be such a big deal, but if there is any traffic, debris will build up requiring it to be cleaned. I've seen other models that have the air intake about 5 inches up the side of the tank, ensuring any ground debris won't cause a problem and therefore not requiring the use of or cleaning of a dust guard. I give this an overall rating of 5 based on 1 good (gas valve), 1 bad (dust guard) and 1 neutral (installation) rating about specific characteristics that i think are important. Obviously I won't know for a while whether I made the right decision in buying these water heaters, but if the quality and durability are there, I'll gladly take the cleaning of the dust guard without complaints! January 6, 2015
This product is of great quality . This is a great product . That helped lower my energy bill . January 2, 2015
Very Nice Heater Overall this is a nice heater, easy to instal, and the control is very nice, and also easy to operate the fittings coming out of the top were not exactly straight so I had to instal unions on both inlet and outlet, but that was not a big deal. I like the fasct you can replace the anode easily too so extending the life beyond 12 years is possible with routine maintanence January 1, 2015
like the name and looked I have put in several heaters for my self and as favor for others over the years, and this one as been a very easy one for me to install, and at my age now I could not complain. Only problem I had the old heater was 9" shorter than the new one, had to do some adjustment, lucky I was handy man enough to do my self. I would need more time to see how it is on my energy bill, and so forth so far 2 days been great! December 19, 2014

Owners Manual
Comprehensive information about your new appliance - from getting started to cleaning and maintenance - with answers to frequently asked questions.

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Troubleshooting & Repair

IMPORTANT - Read and follow the printed Installation Instructions that came with your water heater. The printed Instructions and product labels contain model-specific information, important warnings and safety notices. If you lack the necessary skills to install, troubleshoot or repair the water heater, get help from a qualified person.

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