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Warranty: 15-year limited

Super High Efficiency

Family Size: 5+ People

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A.O. Smith Signature Series 6.6-GPM 160000-BTU Indoor Liquid Propane Ultra-Low NOx Tankless Water Heater

Name: A.O. Smith Signature Series 6.6-GPM 160000-BTU Indoor Liquid Propane Ultra-Low NOx Tankless Water Heater
Brand: A.O. Smith
SKU: 1000601645
Rating: 4.1 (29 reviews)

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4.1

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BTU Rating: 160000

160000

199000

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A. O. Smith's Signature Series liquid propane water heater uses up to 160,000 BTU/h of propane to deliver a 6.6-gallons-per-minute flow rate (based on a 35°F rise) of continuous hot water when sized appropriately. This makes it suitable for whole-home applications, and since it only heats water when needed, it's exceptionally energy-efficient. This condensing indoor model operates at a 0.95 Uniform Energy Factor (UEF) to reduce energy consumption and save money on energy bills. Additionally, you can easily mount your compact water heater on an indoor wall, saving you valuable storage space. High-efficiency tankless propane water heaters have special installation requirements. Professional installation is required. Call 1-877-GOLowes to get this water heater installed.

Delivers hot water for up to 2 showers and 3 sinks when sized appropriately (based on a 0.5 GPM faucet and a 2.5 GPM showerhead in the southern zone)
Operates at a 0.95 Uniform Energy Factor (UEF) for maximum energy efficiency and cost savings
Frees up valuable storage space with compact, indoor wall-mounted design
Professional installation required - call 877-GO-LOWES
Uses 1/2 inch gas line up to 10 feet or 3/4 inch gas line for longer lengths
Features integrated controls for easy temperature control and troubleshooting
Copper primary heat exchanger and stainless steel secondary heat exchanger improve heat transfer and protection to extend the heater's life span
Worry-free safety features include freeze, overheat and surge protection as well as troubleshooting diagnostic codes
Provides peace of mind with a 15-year limited heat exchanger guarantee, 5-year parts guarantee and a 1-year limited labor warranty

General
Type	Tankless	Power Source	Gas
Fuel Type	Liquid propane	Use Location	Indoor
Grade	Residential	Installation Type	Wall mount
Ignition Type	Electric	Series Name	Signature Series
Vent Type	PVC/ABS/CPVC

Dimensions
Vent Diameter(s)	3-in	Width (Inches)	17.75
Depth (Inches)	11.25	Family Size	5
Height (Inches)	23.63	Water Connection Size	3/4-in
Weight (lbs.)	70

Features
Maximum Gallons per Minute	6.6	Grid Capable	No
Point of Use	No	Scale Prevention	No
Annual Fuel Utilization Efficiency % (Percentage)	0	Installation Location	N/A (Portable)
Uniform Energy Factor	.94	Wattage (Watts)	0
BTU Rating	160000	High Efficiency	No
Super High Efficiency	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	15-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

Check out the Best Selling Water Heaters on Lowes.com

Review

4.1 out of 5

29 Reviews

3 Star

77% Recommend this product

Ratings may include incentivized customer reviews.

29 Customer Reviews

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Returned Product Sold as NEW!

Would Not Recommend

Have to return this the box looked new, I got home and it has been installed prior. I had to return it and buy something else.

DontJune 3, 2025
Verified Purchaser

Was this Review Helpful ?

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 4, 2025

Choose Another Brand

Would Not Recommend

Code 111 third month of new home build. You have to line up your own plumber and even though I purchased the extended warranty, I was only reimbursed a partial amount. They sent the part no charge. It worked fine for 2 more months and now code 121. Called support agin and explained problem and at this point what were they going to do to take care of this issue. (Rep) Kacey put it back on me and told me I was going to have to get a plumber to come out and test gas pressure, which I have to pay fo...

GerryApril 1, 2025
From Signature Series 10-GPM 199000-BTU Indoor Liquid Propane Tankless Water Heater

Was this Review Helpful ?

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.c...

Published by the A. O. Smith TeamApril 11, 2025

Lowes sold me a used water heater as new!

Would Not Recommend

Picked it up curbside, my first mistake - Got it home the box was wet, water came out of the unit when I was installing it and the dip switches were marked and set in positions not in the booklet. Went to code 101 in 2 minutes and 991 in less than 5. Reset the unit and the fan is still all over the place. Seems like a pretty expensive item to send out the door after it was obviously returned. It will be returned too!

DanBJanuary 4, 2025
Verified Purchaser

Was this Review Helpful ?

Response from Published by the A. O. Smith Team

We are very 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 TeamJanuary 6, 2025

Easy to install

Would Recommend

Very easy to install. We replaced a 40-gallon propane water heater with this one and are happy with the performance.

MitchApril 26, 2024
Verified Purchaser

Was this Review Helpful ?

I have no idea. It’s not hooked up yet

Would Recommend

A.O.Smith name recognition. Not completely finished so I’m not sure how it’s going to work

BarneyAugust 27, 2023
Verified PurchaserIncentivized

Was this Review Helpful ?

Works as designed

Would Recommend

Great unit for a new guest cottage that we built. On demand is just we need when we have guests.

AllieFebruary 13, 2023

From aosmith.com

Would buy again

Would Recommend

This is my 2nd AO Smith tankless water heater. Bought this one for a 580 sqft cabin.

RayDeanMay 24, 2022
Verified Purchaser

Was this Review Helpful ?

Reliable, quiet operation

I had my first one 10 years with no problems ever. Lightning ran in during storm and damaged the electronics. Thankfully the unit hadn’t changed design and was an easy replacement. I have another brand also, it sometimes drops out with low water pressure.

Dereke84May 2, 2022

From aosmith.com

Quiet and compact

Would Recommend

I appreciated how small it was and how quiet it is when operating.

Bruce65March 20, 2022

From aosmith.com

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