Rheem SPEX4208T
0.98 UEF DOE CCD · 2026-09-19Grade D: 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).
If you are checking the Rheem SPEX4208T, this electric tankless unit uses 603 kWh of electricity a year. That figure applies to the very small draw pattern, the standard daily hot-water usage DOE tests against. It sits 12 kWh below the 615 kWh median of its class, ranking 10th lowest energy use of 271.
Energy use per year
603 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 10 of 271, lowest energy first.
Solid line: this model (603 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
- 0.98 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
- 0.4 gal/min DOE CCD · 2026-09-19
What it costs to install
$1,311–$1,886 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
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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 0.98 · Grade D Price it on your ZIP
The 603 kWh figure is computed by this site, not taken from the registry. 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 this draw pattern. The registry lists a UEF of 0.98 for the SPEX4208T. The source is the DOE CCD, retrieved 2026-09-19. The figure holds only at the federal test's daily draw. Energy use at other daily draws is not available on this page. Against the 271 models registered as an electric tankless unit at the very small draw pattern, it ranks 10th lowest for energy use. That places it in the lowest quarter of its class. The steps behind the figure are set out in how the annual cost and energy figures are calculated.
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 0.4 for this model. The 603 kWh figure and the 10th rank describe use within that draw pattern only. A home that relies on this unit beyond a single bathroom or sink falls outside the test condition behind these figures. For that case, how much energy the unit would use is not available here. To compare units by other fuels, spaces or sizes, the water heater selector by fuel, space and size filters the registry. To match another model in the same class from a model number, use the same-class replacement search.
The running cost is not stated in this text. It depends on your own utility's electricity tariff, so the page computes it from your ZIP in its own block. That calculation uses the 603 kWh figure at the very small draw pattern. The cost calculator on your own ZIP repeats the step for your rate. At a flat per-kWh rate, the 12 kWh gap to the 615 kWh class median changes cost in proportion to that rate. Under tiered or time-of-use tariffs, the effect of that gap is not available here. The installed-cost range on this page is a modeled range, not a quote. It carries its own source and date, separate from the 2026-09-19 energy data.
DOE CCD · 2026-09-19