A low cost indoor heater for a two bathroom home where price matters more than a long warranty.
Amazon $629.12
A connected indoor heater with full whole home power, though major brands give a longer warranty for similar money.
- 199,000 BTU/hHeating power
- 10.3 GPMMax flow
- 5 yearsHeat exchanger warranty
Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.
- Built in Wi-Fi with app alerts and Alexa support
- Sealed direct vent draws outside air, so it works in a closet
- Low 0.53 GPM activation for small draws
- Priced close to major brands with longer warranties
- 5 year heat exchanger warranty is short
- No published UEF or weight; Mizudo advises against use above 3,000 ft
How it scores
The rating comes from 4 measured or published factors, each scored 0-100 against fixed reference points for its fuel. How we rank explains each one.
Specifications
| Model number | WCIU-HW199A1G-NG-M0 |
|---|---|
| Heating | |
| Fuel | Gas |
| Gas type | Natural gas or propane |
| Gas input | 199,000 BTU/h |
| Max flow | 10.3 GPM |
| Condensing | No |
| Installation | |
| Venting | Indoor |
| Vent type | 3 in x 5 in concentric |
| Features | |
| Built-in recirculation | No |
| Wi-Fi | Yes |
| Heat exchanger warranty | 5 years |
| Parts warranty | 2 years |
Alternatives in this fuel
A budget condensing heater for natural gas homes that want PVC venting and lower gas bills, if you can live with an unclear warranty.
ThermoMate $1,099.99A good outdoor heater for a one or two bathroom home in a mild climate.
Amazon $884.10 Amazon $884.10Compare
Compare the Mizudo GEN 3 199K with any other tankless water heater →
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