State ATM-140M-N 1**
State ATM-140M-N 1** is in the DOE listing as of Oct 19, 2026. State ATM-140M-N 1** is in the ENERGY STAR list as of Oct 19, 2026.
- Gas tankless water heater
- 2 listed models
Its figures are also listed under A. O. Smith ATM-140M-N 1**.
Certified figures
- Flow at a 67°F rise
- 4.1gallons per minute
- UEF
- 0.95Uniform energy factor
Your fixtures at once
Change your hour and flowFlow where you live
A bigger rise from colder incoming water leaves the heater with less flow.
- Cold water
- Cold water must be at least 10°F colder than the hot water setting.
- Flow estimate
- The estimate uses the lowest certified flow among the listed models. It is about 3.9 gal/min at a 70°F rise.
Flow limits
- The estimate excludes the flow needed to turn the heater on, heat lost in pipes, and installation.
- Cold water from a well or long pipe run can differ from the temperature you enter.
- Without a stated flow limit, estimates for warmer water may exceed the heater’s actual flow.
Product history
State ATM-140M-N 1** was in the DOE listing by Oct 1, 2026.
State ATM-140M-N 1** has a recorded ENERGY STAR market-availability date of Aug 28, 2026. It first appeared in the ENERGY STAR list between February 2026 and October 2026.
Certified figures by listed model
| Model number | UEF | Flow at a 67°F rise (gal/min) | Recovery efficiency | Draw pattern |
|---|---|---|---|---|
| STM-140M-N 1** | 0.95 | 4.1 | 97% | High |
| STM-140X3-N 1** | 0.95 | 4.1 | 97% | High |
UEF is the uniform energy factor. A dash means the model has no such figure.
ENERGY STAR certified models
| Model number | UEF | Flow at a 67°F rise (gal/min) | Recovery efficiency |
|---|---|---|---|
| STM-140M-N 1** | 0.95 | 4.1 | 97% |
| STM-140X3-N 1** | 0.95 | 4.1 | 97% |
It heats 4.1 gallons per minute of water by 67°F in the test. The median flow among gas tankless models is 4.8 gallons per minute. Its flow at a 67°F rise trails 368 of the 487 gas tankless models.
Under this basic model, 2 model numbers are ENERGY STAR certified. In the test, 5% of its energy does not reach the hot water (UEF 0.95). In the test, daily hot water use was set to high (its draw pattern). Its UEF is lower than that of 49 of the 399 gas tankless models with its draw pattern. On its draw pattern, the median gas tankless UEF is 0.93. Of the energy it spends heating water, 97% ends up in it (its recovery efficiency).
It is the basic model for STM-140M-N 1** and STM-140X3-N 1**. Its test figures match those of 8 other basic models. Between them, those basic models carry 7 other brand names. For the full group, see the A. O. Smith ATM-140M-N 1** page.
It may qualify for 6 rebate programs in 7 states. Another 2 programs may accept it if it meets their other terms.
Also listed as
They carry every figure in the table above.
Rebates
| Program | State | Status | Program page |
|---|---|---|---|
| SoCalGas High-Efficiency or ENERGY STAR Certified Natural Gas Tankless Water Heaters rebate | CA | May qualify | Its own page |
| Colorado Springs Utilities Water heater rebate (gas storage, gas tankless) | CO | May qualify | Its own page |
| Nicor Gas Energy Efficiency Rebates for Your Home (gas tankless) | IL | May qualify if it meets the other terms | Its own page |
| DTE Energy Water Heaters (gas storage, gas tankless) | MI | May qualify | Its own page |
| Xcel Energy MINNESOTA RESIDENTIAL ENERGY EFFICIENCY PROGRAMS (gas storage, gas tankless) | MN | May qualify | Its own page |
| PSE&G Tankless Water Heaters | NJ | May qualify | Its own page |
| Energy Trust of Oregon Residential Incentives | OR, WA | May qualify | Its own page |
| Focus on Energy (gas tankless) | WI | May qualify if it meets the other terms | Its own page |
Programs change their terms. Check the program's own page before you buy.
- Every State basic model
- Every gas tankless water heater certified at 4.0 to 4.9 gallons per minute
- Every gas tankless water heater
- The most-searched gas tankless models side by side
Not covered
- Advertised figures. We have none on file for this model.