What it delivers
The MIZUDO WCIU-HW199A1G-NG-M0 199,000 BTU Natural Gas Tankless Water Heater is a non-condensing gas tankless with a 199,000 BTU/h burner and a stated maximum flow of 10.3 GPM.
At a 45°F rise (mild inlet water to a 120°F set point) it holds about 6.8 GPM, 3 showers at 2 GPM; in winter, at a 70°F rise, about 4.4 GPM, 2 showers at 2 GPM. Run your house through the planner.
At full fire it burns about 192 cubic feet of natural gas an hour. The gas line has to carry that on top of the furnace, range and dryer; a gas fitter sizes the pipe from its length and the total load.
Non-condensing indoor units run hot exhaust and vent in the maker's listed vent system (often stainless Category III), which costs more than plastic.
The listing describes its venting as: direct-vent.
From the listing: connections: 3/4" npt; connectivity: WiFi; vent size: 5" concentric; material: 10.3 GPM, 199,000 BTU, Indoor; model: WCIU-HW199A1G-NG-M0.
The listing gives dimensions of 15.9 in (W) x 24.8 in (H) and a weight of 55.5 lb.
Right unit for this house?
Install it when
- Houses running 2 showers at once in winter
- Replacing a gas tank heater
Look at another unit when
- More than 2 winter showers at once
- Homes without a gas line
Strengths and trade-offs
Strengths
- 199,000 BTU/h input
- Up to 10.3 GPM
Trade-offs
- Gas pipe sizing to confirm
- Stainless venting costs more
- Needs periodic descaling
Install limits
- Figures are the maker's or seller's own. Flow at a rise is our estimate from the input; gas, venting and electrical work needs a licensed professional.
Rated performance
Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.
| Model number | WCIU-HW199A1G-NG-M0 | Retailer |
|---|---|---|
| Dimensions (seller) | 15.9"W x 24.8"H | Retailer |
| Voltage | 120 V | Retailer |
| Max flow (maker) | 10.3 GPM | Retailer |
| Input (maker) | 199,000 btu_per_hour_per_foot_per_fahrenheit | Retailer |
| Product weight | 55.5 lb | Retailer |
| Material | 10.3 GPM, 199,000 BTU, Indoor | Retailer |
| Fuel | Natural Gas | Retailer |
| Venting | direct-vent | Retailer |
| Connections | 3/4" npt | Retailer |
| Vent size | 5" concentric | Retailer |
| Connectivity | WiFi | Retailer |
Rival units at this flow
More gas tankless water heaters rated for similar demand
- Noritz NR98SVNG Natural Gas Tankless Water Heater
- Eccotemp 6.8GB-NG Natural Gas Outdoor Tankless Water Heater
- Ranein TMYD-01020120 68,000 BTU Propane Outdoor Tankless Water Heater
- Eccotemp 7GB-NG Natural Gas Outdoor Tankless Water Heater
Full gas tankless water heaters spec grid · Every MIZUDO unit in the catalog
Final verdict
A solid non-condensing gas tankless for houses running 2 showers at once in winter.
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