DoesTheMath

Rheem SPEX1812

0.95 UEF DOE CCD · 2026-09-19
F

Grade F: 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 this model, the Rheem SPEX1812 uses 622 kWh a year at the very small draw pattern, the standard daily hot-water usage DOE tests against. That is 7 kWh above the class median of 615 kWh, ranking 152nd lowest of 271 electric tankless units.


Energy use per year

622 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 above the median of 615 kWh for the 271 models registered in the same heater type and draw pattern; it ranks 152 of 271, lowest energy first.

This model: 622 kWh

Solid line: this model (622 kWh). Dashed line: the class median.

Min 562 kWh Median 615 kWh Max 649 kWh

DOE CCD · 2026-09-19

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What it costs to run where you live

Enter your ZIP to see what this unit costs to run a year on your own utility’s electricity rate.


What the registry files

UEF (Uniform Energy Factor) how much hot water you get for each unit of energy the heater uses
0.95 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
0.2 gal/min DOE CCD · 2026-09-19

What it costs to install

$1,303–$1,814 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) · 2026-04-01

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Safety 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 · 2026-09-24

What these figures mean

The registry lists a UEF, the ratio of hot water delivered to energy used, of 0.95 for the Rheem SPEX1812. This site, not the registry, combined that UEF with the DOE test's daily hot-water draw for the very small draw pattern to compute 622 kWh of electricity a year (DOE CCD, retrieved 2026-09-19). Across the 271 models registered as an electric tankless unit at this draw pattern, the median is 615 kWh. This model sits 7 kWh above that median, at 152nd lowest energy use, which places it in the second-highest quarter of its class. The figure applies only at the test draw. Measured use in a particular home is not available from this data.

The very small draw pattern covers small units: a single bathroom, or a point-of-use heater under a sink. That is the situation this figure fits. The registry gives a maximum flow rate in gallons per minute of 0.2 for this model. A load that needs more flow than 0.2 is outside what this listing shows. If your use is closer to a whole home, the 622 kWh does not describe it, and this data has no figure for this model at other draw patterns. The gap to the class median is 7 kWh at the test draw. To compare by fuel, space and size, use the water heater selector, or find a same-class replacement by model number.

The running cost is not stated here because it depends on your own utility electricity tariff. Multiply the 622 kWh by your price per kilowatt-hour, or let the cost calculator do it from your ZIP. The same rate applied to the 7 kWh gap gives the yearly cost difference from the class median of 615 kWh. Both figures hold at the very small draw pattern only. The method behind the annual figure is set out in how the annual cost is calculated. The modeled installed-cost range appears in its own block on this page with its source and date. It is a modeled range, not a quote, and it is not repeated in this text.

DOE CCD · 2026-09-19

How this compares

The closest models in the same class — same fuel, type and draw pattern.


Keep going

UEF 0.95 · Grade F Price it on your ZIP