Midea MGWH150ISNN
0.82 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).
You are checking the Midea MGWH150ISNN, a gas tankless unit. It uses 135 therms of natural gas a year at the medium draw pattern, the standard daily hot-water usage DOE tests against. That is 0 therms from the class median of 135 therms, across 80 models.
Energy use per year
135 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 equal to the median of 135 therms for the 80 models registered in the same heater type and draw pattern; it ranks 32 of 80, lowest energy first.
Solid line: this model (135 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
- 0.82 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
- 3.7 gal/min DOE CCD · 2026-09-19
What it costs to install
$1,745–$2,687 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 Midea model on file
What this brand files, by heater type.
UEF 0.82 · Grade G Price it on your ZIP
The figure of 135 therms was computed by this site, not the registry. It combines the registry's UEF with the DOE test's daily hot-water draw for the medium draw pattern. UEF, the ratio of hot water delivered to energy used, is 0.82 for this model. The figure applies only to natural gas at that draw pattern. Real use in a home can differ from the test's daily draw, and that difference is not available in this data. The source is the DOE CCD, retrieved 2026-09-19. The steps are set out in how the annual cost is calculated.
Among the 80 models registered as a gas tankless unit at the medium draw pattern, this one ranks 32nd lowest in energy use. That puts it in the second-lowest quarter of its class. Its 135 therms equals the class median of 135 therms, so the difference is 0 therms. The figure suits a household whose use matches the medium draw pattern. It fits less well where daily use is far from that draw. The maximum flow rate in gallons per minute is 3.7. Flow under other conditions is not available here. To compare with another unit of the same class, use find a same-class replacement by model number.
The running cost is not stated here because it depends on your state's average residential gas price. The cost calculator on your own ZIP applies that price to the 135 therms figure. At the same gas price, a unit using the class median of 135 therms would cost the same to run as this one. The result holds only for natural gas at the medium draw pattern. For a comparison across fuel, space and size, see the selector by fuel, space and size. A modeled installed-cost range appears in its own block on this page, with its source and date.
DOE CCD · 2026-09-19