Fogatti FDG420OD-CS120S-LP
0.83 UEF DOE CCD · 2026-09-19Grade G: where this UEF sits among the 80 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set
A gas tankless unit, medium draw pattern (a typical three- or four-person household, about 55 gallons on a busy morning).
If you are checking the Fogatti FDG420OD-CS120S-LP, this gas tankless unit uses 134 therms of natural gas a year. That figure applies at the medium draw pattern, the standard daily hot-water usage DOE tests against. It sits 1 therms below the class median of 135 therms, and it has the 28th lowest energy use of 80 models.
Energy use per year
134 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 below the median of 135 therms for the 80 models registered in the same heater type and draw pattern; it ranks 28 of 80, lowest energy first.
Solid line: this model (134 therms). Dashed line: the class median.
Min 114 therms Median 135 therms Max 137 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
- 0.83 DOE CCD · 2026-09-19 Compared only with other models registered as a gas tankless unit at the medium draw pattern.
- Draw Pattern the standard daily usage profile DOE tests the unit against
- Medium DOE CCD · 2026-09-19
- Maximum Gallons Per Minute how many gallons a minute it can heat while running continuously
- 3.3 gal/min DOE CCD · 2026-09-19
What it costs to install
$1,792–$2,743 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 Fogatti model on file
What this brand files, by heater type.
UEF 0.83 · Grade G Price it on your ZIP
The 134 therms figure is calculated by this site. The registry does not list it. It combines the registry's UEF, the ratio of hot water delivered to energy used, with the DOE test's daily hot-water draw for the medium draw pattern. For this model the UEF is 0.83. The medium pattern stands for the daily use of a typical mid-sized household. So 134 therms holds only at that test draw, with natural gas as the fuel. A home that uses more hot water than the test assumes will burn more gas. A home that uses less will burn less. The underlying data come from DOE CCD, retrieved 2026-09-19. The full steps are in how this site calculates annual energy and cost.
The class here is the 80 models registered as a gas tankless unit at the medium draw pattern. Within that class, this model has the 28th lowest energy use. The class median is 135 therms, so this unit sits 1 therms below it at the test draw. That puts it in the second-lowest quarter of its class for energy use. With a gap of 1 therms, its yearly gas use at the test draw is close to the class median. The figure fits a home whose daily use is near the medium pattern. For a home far from that pattern, 134 therms does not describe its gas use. The maximum flow rate in gallons per minute is 3.3. This data does not show whether 3.3 covers several fixtures running at once in a given home. To compare other units in this class, use the same-class replacement search by model number.
This text does not state a running cost. The cost of 134 therms of natural gas a year depends on your state's average residential gas price. For that reason, the page works out the cost from your ZIP instead of giving one figure for every reader. You can check the result with the running-cost calculator for your own ZIP. The 28th rank and the 1 therms gap to the median describe energy use at the medium draw pattern, not cost. Homes in different states can pay different amounts for the same 134 therms when their gas rates differ. The installed price range appears in its own block, with its source and date. It is a modeled installed-cost range, not a quote.
DOE CCD · 2026-09-19