What it delivers
The Rinnai RE180iN Natural Gas Tankless Water Heater is a non-condensing gas tankless with a 180,000 BTU/h burner and a stated maximum flow of 8.5 GPM.
At a 45°F rise (mild inlet water to a 120°F set point) it holds about 6.2 GPM, 3 showers at 2 GPM; in winter, at a 70°F rise, about 4.0 GPM, 1 shower at 2 GPM. Size it to your fixtures and climate.
The line must deliver about 174 cubic feet of natural gas an hour when it fires flat out. The requirement calculator adds it up; a licensed fitter confirms the pipe.
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.
From the listing: features: LED Display; connectivity: WiFi; material: Stainless Steel; model: RE180iN; warranty: 1 Year Labor, 5 Year Parts.
The listing gives dimensions of 14.05 in (W) x 27.28 in (H) and a weight of 24.49 kg.
Warranty, per the listing: 1 Year Labor, 5 Year Parts.
Right unit for this house?
Install it when
- One shower at a time in cold climates
- Replacing a gas tank heater
Look at another unit when
- More than 1 winter shower at once
- Homes without a gas line
Strengths and trade-offs
Strengths
- 180,000 BTU/h input
- Up to 8.5 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 | RE180iN | Retailer |
|---|---|---|
| Dimensions (seller) | 14.05"W x 27.28"H | Retailer |
| Features (seller) | LED Display | Retailer |
| Voltage | 120 V | Retailer |
| Max flow (maker) | 8.5 GPM | Retailer |
| Input (maker) | 180,000 BTU/h | Retailer |
| Product weight | 24.49 kg | Retailer |
| Material | Stainless Steel | Retailer |
| Warranty | 1 Year Labor, 5 Year Parts | Retailer |
| Fuel | Natural Gas | Retailer |
| Condensing | non-condensing | Retailer |
| Connectivity | WiFi | Retailer |
Rival units at this flow
More gas tankless water heaters rated for similar demand
- SNDOAS IF.JSQ25-B13NA Natural Gas Tankless Water Heater
- VEVOR JSQ30-A 100,000 BTU Tankless Water Heater
- SNDOAS IF.JSQ30-W16NA 102,000 BTU Natural Gas Tankless Water Heater
- VancEpic VH10KR-NG 100,000 BTU Natural Gas Tankless Water Heater
Full gas tankless water heaters spec grid · Every Rinnai unit in the catalog
Final verdict
A solid non-condensing gas tankless for one shower at a time in cold climates.
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