Laars LT199NRX1
Laars LT199NRX1 is a gas tankless water heater from Laars rated 5.8 GPM at a 0.96 UEF.
| Uniform Energy Factor (UEF) | 0.96 |
|---|---|
| Annual gas use (natural gas) | 176 therms/yr |
| Recovery efficiency | 98 % |
| Annual propane use | 192.35 gal/yr |
| Fuel | Natural Gas |
|---|
| Max flow rate | 5.8 GPM |
|---|---|
| Draw pattern | High |
| Minimum activation flow | 0.5 GPM |
| Gas input rate | 199 kBTU/h |
|---|
| Max current draw | 2 A |
|---|---|
| Vent type | Power Direct Vent |
| Vent size | 2 / 3 |
| Smart / connected capable | No |
|---|
| Width | 17.3 in |
|---|---|
| Depth | 14.8 in |
| ENERGY STAR certified | Yes |
|---|
Real flow rate by climate
A tankless heater's usable flow depends on how far it must raise incoming water temperature. Sustained hot-water flow of the Laars LT199NRX1 at common temperature rises (a typical shower uses about 2 GPM of mixed water):
| Temperature rise | Climate | Sustained flow | Simultaneous showers |
|---|---|---|---|
| 45 °F | Warm climate (~75 °F groundwater) | 5.8 GPM | 2 |
| 55 °F | Mild climate (~65 °F groundwater) | 5.8 GPM | 2 |
| 70 °F | Cold climate (~50 °F groundwater) | 5.5 GPM | 2 |
| 77 °F | DOE test condition | 5 GPM | 2 |
Similar water heaters
- A. O. Smith ACTH-199M-(N,P) 1 (UEF 0.95)
- A. O. Smith T-H3-OS-N 1 (ACT-199O-N 1) (UEF 0.95)
- A. O. Smith T-H3-OS-N 1 (ACT-199O-P 1-1) (UEF 0.95)
- A. O. Smith T-H3-OS-N 1 (ATO-540H 1) (UEF 0.95)
- A. O. Smith T-H3-OS-N 1 (ATO-540H 1-1) (UEF 0.95)
- A. O. Smith T-H3-OS-N 1 (ATO-540HX3-N 1) (UEF 0.95)
Frequently asked questions
Is the Laars LT199NRX1 ENERGY STAR certified?
Yes, the Laars LT199NRX1 holds a current ENERGY STAR certification for water heating efficiency (UEF 0.96).
How much does the Laars LT199NRX1 cost to run per year?
About $255 per year at national average energy rates, based on its certified annual energy use under the DOE test draw pattern. Your rate and usage change this figure.
What venting does the Laars LT199NRX1 use?
The Laars LT199NRX1 uses Power Direct Vent venting with 2 / 3 in vent connections. Matching the existing vent type is usually the cheapest replacement path.
Is the Laars LT199NRX1 a smart water heater?
No, the Laars LT199NRX1 is not connected-capable — it has no app connectivity or demand-response support.
Sources
- data.energystar.gov (retrieved 2026-07-17)