A whole home indoor heater for buyers who want maximum burner size without the condensate drain of a condensing unit.
Amazon $1,201.29
A low cost indoor whole home heater for natural gas homes, but check the warranty with ThermoMate before buying.
- 199,000 BTU/hHeating power
- 8 GPMMax flow
- 0.81UEF
Price checked October 31, 2026. As an Amazon Associate we earn from qualifying purchases.
- 199,000 BTU/h indoor heater for under $750
- Compact 21 in tall body fits a utility room wall
- Plugs into a standard 120 V outlet
- No published warranty terms on the product page
- Natural gas only
- The 8 GPM figure assumes warm 72°F inlet water, so winter flow will be much lower
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 | CZ750NG |
|---|---|
| Heating | |
| Fuel | Gas |
| Gas type | Natural gas |
| Gas input | 199,000 BTU/h |
| Max flow | 8 GPM |
| UEF | 0.81 |
| Condensing | No |
| Installation | |
| Venting | Indoor |
| Vent type | 3 in OD vent |
| Features | |
| Built-in recirculation | No |
| Wi-Fi | No |
Alternatives in this fuel
A budget indoor heater from a major brand for a two bathroom home in a moderate climate.
Amazon $653.77 Amazon $785.13A premium condensing heater for a large home that wants top efficiency and app control from one unit.
Amazon $1,847.43 Amazon $1,859.99Compare
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