Friedrich RTGH-S11I
Friedrich RTGH-S11I is in the DOE listing as of Oct 19, 2026. Friedrich RTGH-S11I is in the ENERGY STAR list as of Oct 19, 2026.
- Gas tankless water heater
- 2 listed models
Its figures are also listed under Bradford White KGWH-190JFN.
Certified and advertised figures
- Flow at a 67°F rise
- 5.8gallons per minuteCertified
- Advertised flow
- 11.2gallons per minuteFriedrich, at a 35°F rise
- UEF
- 0.96Uniform energy factor
Your fixtures at once
Change your hour and flowFlow where you live
Colder incoming water needs a bigger rise, so the heater gives 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 5.6 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
Friedrich RTGH-S11I was in the DOE listing by Oct 1, 2026.
Friedrich RTGH-S11I has a recorded ENERGY STAR market-availability date of Aug 1, 2022. It first appeared in the ENERGY STAR list between June 2024 and July 2024.
Advertised and certified figures
| Figure | Advertised | Certified | Advertiser | Read |
|---|---|---|---|---|
| UEF | 0.96 | 0.96 | Friedrich | Read Oct 4, 2026 |
| Flow | 11.2 gal/min at a 35°F rise | 5.8 gal/min at a 67°F rise | Friedrich | Read Oct 4, 2026 |
| Flow | 8.8 gal/min at a 45°F rise | 5.8 gal/min at a 67°F rise | Friedrich | Read Oct 4, 2026 |
| Flow | 5.9 gal/min at a 67°F rise | 5.8 gal/min at a 67°F rise | Friedrich | Read Oct 4, 2026 |
Certified figures by listed model
| Model number | UEF | Flow at a 67°F rise (gal/min) | Recovery efficiency | Draw pattern |
|---|---|---|---|---|
| FDTGH-S11I | 0.96 | 5.8 | 98% | High |
| FDTGH-SR11I | 0.96 | 5.8 | 98% | 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 |
|---|---|---|---|
| FDTGH-S11I | 0.96 | 5.8 | 98% |
| FDTGH-SR11I | 0.96 | 5.8 | 98% |
At a 67°F rise, its flow in the test is 5.8 gallons per minute. The median flow among gas tankless models is 4.8 gallons per minute. Of 487 gas tankless models, 26 have a higher flow than this one.
It has 2 model numbers that are ENERGY STAR certified. In tests, 96% of the energy it uses ends up as hot water (UEF 0.96). In the test, daily hot water use was set to high (its draw pattern). Of 399 gas tankless models with the same draw pattern, 15 have a higher UEF. For its type and draw pattern, the median UEF is 0.93. While it heats water, 98% of the energy used goes into the water (its recovery efficiency).
It is sold as FDTGH-S11I and FDTGH-SR11I. Its test figures match those of 8 other basic models. Between them, those basic models carry 6 other brand names. For the full group, see the Bradford White KGWH-190JFN page.
It may qualify for 6 rebate programs in 7 states. Another 2 rebate 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 Friedrich basic model
- Every gas tankless water heater certified at 5.0 to 5.9 gallons per minute
- Every gas tankless water heater
- The most-searched gas tankless models side by side
Not covered
- Changes to an advertised figure after the date beside it.