What it delivers
The Rinnai RX180iN Condensing Tankless Water Heater is a condensing gas tankless with a 180,000 BTU/h burner and a stated maximum flow of 10.0 GPM.
At a 45°F rise (mild inlet water to a 120°F set point) it holds about 7.6 GPM, 3 showers at 2 GPM; in winter, at a 70°F rise, about 4.9 GPM, 2 showers at 2 GPM. Run your house through the planner.
Gas load at full fire: about 2.0 gallons of propane an hour. An older half-inch line that already feeds a furnace often can't spare that, so have a gas fitter check the pipe size and run.
It recovers heat from its own exhaust, so it runs plastic venting and needs a condensate drain; check the vent lengths its manual allows.
From the listing: connectivity: WiFi; material: Copper, Stainless Steel; model: RX180iN; warranty: 5 Year Labor, 5 Year Parts.
The listing gives dimensions of 19 in (W) x 31 in (H), a weight of 54 lb and mount in the box.
Warranty, per the listing: 5 Year Labor, 5 Year Parts.
Right unit for this house?
Install it when
- Houses running 2 showers at once in winter
- Propane homes
- 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
- 180,000 BTU/h input
- Up to 10.0 GPM
- Condensing efficiency
Trade-offs
- Needs a gas line sized for the load
- Needs a condensate drain
- 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 | RX180iN | Retailer |
|---|---|---|
| Dimensions (seller) | 19"W x 31"H | Retailer |
| Features (seller) | Wi-Fi Capabilities, Compact Size, High Energy Efficiency, Indoor/Outdoor Installation | Retailer |
| Voltage | 120 V | Retailer |
| Max flow (maker) | 10 GPM | Retailer |
| Input (maker) | 180,000 BTU/h | Retailer |
| Product weight | 54 lb | Retailer |
| Material | Copper, Stainless Steel | Retailer |
| Warranty | 5 Year Labor, 5 Year Parts | Retailer |
| Fuel | propane | Retailer |
| Condensing | condensing | Retailer |
| Connectivity | WiFi | Retailer |
Rival units at this flow
More gas tankless water heaters rated for similar demand
- Ranein RH12KG-C-NG 120,000 BTU Natural Gas Condensing Tankless Water Heater
- ThermoMate CZ480NG Natural Gas Condensing Tankless Water Heater
- Rheem RTGH-84DVLN-3 157,000 BTU Natural Gas Condensing Tankless Water Heater
- Rinnai RX130iN Condensing Tankless Water Heater
Full gas tankless water heaters spec grid · Every Rinnai unit in the catalog
Final verdict
A solid condensing gas tankless for houses running 2 showers at once in winter.
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