Hot Water List

Lochinvar TK-510C-NI 1**

Lochinvar TK-510C-NI 1** is in the DOE listing as of Oct 19, 2026.

  • Gas tankless water heater
  • 1 listed model

Not listed as ENERGY STAR certified on Oct 19, 2026.

Its figures are also listed under A. O. Smith TK-510C-NI 1**.

Certified and advertised figures

Flow at a 67°F rise
4.7gallons per minuteCertified
Advertised flow
10.0gallons per minuteLochinvar, up to, no rise stated
UEF
0.81Uniform energy factor

Flow where you live

The heater gives less flow when colder incoming water needs a bigger rise.

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 4.5 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.

Advertised and certified figures

Lochinvar TK-510C-NI 1**: advertised and certified
Lochinvar TK-510C-NI 1**: advertised and certified UEF: advertised 0.81, certified 0.81. UEF: advertised 0.81, certified 0.81 (advertised up to). Flow: advertised 10.0 gal/min, certified 4.7 gal/min (advertised up to, no rise stated, certified at a 67°F rise). Flow: advertised 4.7 gal/min, certified 4.7 gal/min (advertised at a 67°F rise, certified at a 67°F rise). UEF Advertised 0.81 Certified 0.81 UEF · advertised up to Advertised 0.81 Certified 0.81 Flow · advertised up to, no rise stated, certified at a 67°F rise Advertised 10.0 gal/min Certified 4.7 gal/min Flow · advertised at a 67°F rise, certified at a 67°F rise Advertised 4.7 gal/min Certified 4.7 gal/min
Lochinvar TK-510C-NI 1**: advertised figures, where and when read
FigureAdvertisedCertifiedAdvertiserRead
UEF 0.81 0.81 Lochinvar Read Oct 4, 2026
UEF up to 0.81 0.81 Lochinvar Read Oct 4, 2026
Flow up to 10.0 gal/min, no rise stated 4.7 gal/min at a 67°F rise Lochinvar Read Oct 4, 2026
Flow 4.7 gal/min at a 67°F rise 4.7 gal/min at a 67°F rise Lochinvar Read Oct 4, 2026

See how advertised flow compares across tankless models

Certified figures by listed model

Lochinvar TK-510C-NI 1**: certified figures by listed model
Model numberUEFFlow at a 67°F rise (gal/min)Recovery efficiencyDraw pattern
LTI-510C 1**0.814.782%High

UEF is the uniform energy factor. A dash means the model has no such figure.

It heats 4.7 gallons per minute of water by 67°F in the test. The median gas tankless model heats 4.8 gallons per minute by 67°F. Its flow at a 67°F rise trails 252 of the 487 gas tankless models.

On Oct 19, 2026, this heater was not listed as ENERGY STAR certified. In tests, 81% of the energy it uses ends up as hot water (UEF 0.81). Its test simulated a day of high hot water use (its draw pattern). Among 399 gas tankless models on its draw pattern, 327 have a higher UEF. A UEF of 0.93 is the median for its type and draw pattern. Of the energy it spends heating water, 82% ends up in it (its recovery efficiency).

Its test figures match those of 5 other basic models. Each of them is listed under a different brand. For the full group, see the A. O. Smith TK-510C-NI 1**.

Also listed as

They carry every figure in the table above.

Updated Oct 19, 2026 · Methodology

Not covered

  • Changes to an advertised figure after the date beside it.