Rheem SPEX3208
0.97 UEF DOE CCD · 2026-09-19Grade E: where this UEF sits among the 271 models in its class, lowest (G) to highest (A). A position, not an official label. How the grade is set
An electric tankless unit, very small draw pattern (small units - a single bathroom, or a point-of-use heater under a sink).
Checking the Rheem SPEX3208? This electric tankless unit uses 609 kWh a year at the very small draw pattern, the standard daily hot-water usage DOE tests against. That is 6 kWh below the 615 kWh class median, ranking 37th lowest of 271 for energy use.
Energy use per year
609 kWh 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 electricity rate where you live.
That is below the median of 615 kWh for the 271 models registered in the same heater type and draw pattern; it ranks 37 of 271, lowest energy first.
Solid line: this model (609 kWh). Dashed line: the class median.
Min 562 kWh Median 615 kWh Max 649 kWh
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
- 0.97 DOE CCD · 2026-09-19 Compared only with other models registered as an electric tankless unit at the very small draw pattern.
- Draw Pattern the standard daily usage profile DOE tests the unit against
- Very small DOE CCD · 2026-09-19
- Maximum Gallons Per Minute how many gallons a minute it can heat while running continuously
- 0.3 gal/min DOE CCD · 2026-09-19
What it costs to install
$1,309–$1,862 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 electric tankless water heaters
Electric instantaneous units, sized by flow rate rather than tank gallons.
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Every Rheem model on file
What this brand files, by heater type.
UEF 0.97 · Grade E Price it on your ZIP
The annual figure of 609 kWh for the Rheem SPEX3208 is not a registry entry. This site computed it from the registry's UEF, the ratio of hot water delivered to energy used, which is 0.97 for this model, and the DOE test's daily hot-water draw for the very small draw pattern. The source data was retrieved from the DOE CCD on 2026-09-19. The class median is 615 kWh, so this model sits 6 kWh below it. The data does not show how that difference would appear on a bill, and the figure applies only to electricity at this draw pattern.
The very small draw pattern covers small units: a single bathroom, or a point-of-use heater under a sink. The registry lists a maximum flow rate in gallons per minute of 0.3 for this model. Among the 271 models registered as an electric tankless unit at this draw pattern, this one ranks 37th lowest for energy use, which places it in the lowest quarter of its class. The figure does not describe a household that draws more hot water than the test assumes. Energy figures for other draw patterns are not available on this page, and none is estimated here.
Running cost is not written in the text because it depends on your own utility electricity tariff. The cost calculator applies your ZIP to the 609 kWh figure, and how the annual cost is calculated describes the method. The installed price range appears in its own block on this page as a modeled range, not a quote. If you are checking a swap, you can find a same-class replacement by model number and compare it with this model's position of 37th lowest among 271. Actual use in a given home can differ from the test's daily draw, and this data cannot measure that.
DOE CCD · 2026-09-19