NAVIEN NHW700-199SU-NG
0.81 UEF DOE CCD · 2026-09-19Grade G: where this UEF sits among the 397 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set
A gas tankless unit, high draw pattern (a larger household, or one where showers and laundry overlap).
If you are verifying the NAVIEN NHW700-199SU-NG, this gas tankless unit uses 209 therms of natural gas a year. That figure holds at the high draw pattern, the standard daily hot-water usage DOE tests against. It sits 27 therms above the 182 therms class median, ranking 323rd lowest of 397.
Energy use per year
209 therms a year
Computed by this site from the registry's UEF and the federal test's daily hot-water draw for this draw pattern. What it costs depends on the natural gas rate where you live.
That is above the median of 182 therms for the 397 models registered in the same heater type and draw pattern; it ranks 323 of 397, lowest energy first.
Solid line: this model (209 therms). Dashed line: the class median.
Min 173 therms Median 182 therms Max 209 therms
What it costs to run where you live
What the registry files
- UEF (Uniform Energy Factor) how much hot water you get for each unit of energy the heater uses
- 0.81 DOE CCD · 2026-09-19 Compared only with other models registered as a gas tankless unit at the high draw pattern.
- Draw Pattern the standard daily usage profile DOE tests the unit against
- High DOE CCD · 2026-09-19
- Maximum Gallons Per Minute how many gallons a minute it can heat while running continuously
- 5.1 gal/min DOE CCD · 2026-09-19
What it costs to install
$1,698–$2,632 installed
Not a quote — a modeled range of what installers have charged for this class of unit; your price will vary with labor rates, access, and local code requirements.
Escalation indexes: equipment (BLS PPI) latest available: August 2026; labor (BLS ECI) latest available: April 2026 to June 2026.
NLR REMDB (BLS PPI/ECI escalated) · 2026-04-01Safety record
No CPSC recall names this model.
Checked against the CPSC recall database. CPSC does not publish a model-level match for this product category, so this list is curated by hand from the manufacturer's recall filings.
CPSC · 2026-09-24What these figures mean
How this compares
The closest models in the same class — same fuel, type and draw pattern.
Keep going
How every figure on this page is calculated
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Find what replaces your water heater
Enter the model number off your old unit and see what is on file today, with the yearly cost difference.
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Find a water heater that fits
Three questions — fuel, hot water need, install space — narrow every model on file to the ones that fit.
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What a water heater costs to run
Prices a unit's efficiency against your own utility's filed tariff for your ZIP code.
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How to size a tankless water heater by GPM
Answered from what models in this size actually file.
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Water heaters
Every model on file with the Department of Energy, by heater type.
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All gas tankless water heaters
Gas-fired instantaneous units, sized by flow rate rather than tank gallons.
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Every NAVIEN model on file
What this brand files, by heater type.
UEF 0.81 · Grade G Price it on your ZIP
This site computed the 209 therms figure; the registry does not publish an annual energy value for this model. We combined the registry's UEF, the ratio of hot water delivered to energy used, with the DOE test's daily hot-water draw. That draw is the one DOE sets for the high draw pattern. For the NHW700-199SU-NG, the UEF is 0.81. The inputs come from the DOE Compliance Certification Database, retrieved 2026-09-19. The figure therefore describes the test's daily draw, not any particular home. A home that uses more hot water than the test assumes will use more gas, and one that uses less will use less. The page on how the annual cost is calculated sets out each step.
The high draw pattern describes a larger household, or one where showers and laundry overlap. That is the usage this unit was rated for. Its maximum flow rate in gallons per minute is 5.1. Whether that flow covers a given home depends on how many outlets run at once, and the registry does not record that. Within the 397 gas tankless models at the high draw pattern, this unit ranks 323rd lowest in energy use. That places it in the highest quarter of its class for energy use. A reader who wants lower annual gas use at the same draw pattern will find most models in this class below it. To compare with models in the same class, find a same-class replacement by model number.
This text states no running cost for the NHW700-199SU-NG. The cost depends on the average residential gas price in the reader's state. The page computes it from the reader's ZIP, applying that rate to 209 therms a year at the high draw pattern. The 27 therms gap above the class median carries into that cost at the same rate. To see the cost on your own rate, enter a ZIP in the cost calculator for your own ZIP. The page does not know your household size or actual hot-water use. The cost shown therefore still assumes the test's daily draw. The installed price range sits in its own block on this page, with its source and date. It is a modeled range, not a quote.
DOE CCD · 2026-09-19