If you are shopping for a tankless water heater, Rinnai and Rheem are the two names you will see everywhere. Both are legitimate brands with long track records but they are built for different buyers. Rinnai is the premium, contractor-grade option. Rheem is the value play widely stocked at big-box stores. The right choice depends on your fuel type, demand, and budget.
This guide breaks down the real differences: model specs, UEF ratings, pricing, warranties, and which one to buy.
Rinnai vs. Rheem Tankless Water Heater: Quick Comparison
| Feature | Rinnai | Rheem |
|---|---|---|
| Best For | High-demand homes, cold climates | Budget buyers, mild climates, DIY |
| Unit Price Range | $800-$1,800 | $500-$1,400 |
| Top UEF Rating (gas) | 0.96 (RUR199iN) | 0.96 (RTGH-95DVLN) |
| Max Flow Rate (gas) | 11.1 GPM | 9.5 GPM |
| Heat Exchanger | Stainless steel / copper-alloy | Copper |
| Recirculation | Built-in (V-series) | Select models only |
| Heat Exchanger Warranty | 12 years | 12 years |
| Parts Warranty | 5 years | 5 years |
| Smart Home | Rinnai Control-R | Rheem EcoNet |
| Big-Box Availability | Limited | Yes (Home Depot) |
Rinnai Tankless Water Heaters: Model Breakdown
Rinnai RL Series (Entry-Level Gas)
The RL75iN tops out at 7.5 GPM with a UEF of 0.82. The RL94iN pushes 9.4 GPM at 0.82 UEF. These are non-condensing units that vent hot exhaust and are cheaper to install with existing Category III stainless flue systems. Unit cost: $800-$1,100.
Rinnai RUR / RUS Series (Condensing)
The RUR199iN is Rinnai’s flagship: 11.1 GPM, UEF 0.96, and built-in recirculation with a pump. Buy this for large households, cold groundwater, or multiple simultaneous demands (shower + dishwasher + laundry). Unit cost: $1,300-$1,800. See our guide on whether tankless water heaters actually save money to check if the upgrade pencils out for you.
Rinnai RSC Series (Propane)
For propane homes, the RSC series mirrors the RUR performance specs. Propane operating costs run about 2x natural gas at current rates.
Rinnai vs. Navien and Rinnai vs. Noritz
If you are also comparing Rinnai against other premium brands, see our full Rinnai vs. Navien comparison and Rinnai vs. Noritz breakdown.
Rheem Tankless Water Heaters: Model Breakdown
Rheem’s advantage is accessibility. You can buy at Home Depot, get same-day delivery, and find a plumber who has installed one before without hunting.
Rheem RTEX Series (Electric)
The RTEX-36 handles most 3-bath homes on a 240V/150A supply. UEF hits 0.99. Unit cost: $500-$800. For a full comparison, see our electric vs. gas water heater cost comparison.
Rheem RTGH Series (Gas Condensing)
The RTGH-95DVLN: 9.5 GPM, UEF 0.96, dual PVC venting, EcoNet Wi-Fi. Competes with Rinnai’s RUR series on efficiency but falls short on flow rate for large homes. Unit cost: $900-$1,400. For Rheem vs. other tank brands, see our Rheem vs. AO Smith comparison.
Rheem RTG Series (Non-Condensing Gas)
The RTG-70XLN and RTG-84XLN are non-condensing, Category III venting, UEF around 0.82. Good retrofit choice where existing flue infrastructure is in place. Unit cost: $600-$900.
UEF Ratings Side by Side
| Model | Brand | Fuel | Max GPM | UEF | Unit Price |
|---|---|---|---|---|---|
| RUR199iN | Rinnai | Natural Gas | 11.1 | 0.96 | $1,300-$1,800 |
| RUS199iN | Rinnai | Natural Gas | 11.1 | 0.96 | $1,200-$1,700 |
| RL94iN | Rinnai | Natural Gas | 9.4 | 0.82 | $900-$1,100 |
| RTGH-95DVLN | Rheem | Natural Gas | 9.5 | 0.96 | $1,000-$1,400 |
| RTG-84XLN | Rheem | Natural Gas | 8.4 | 0.82 | $700-$900 |
| RTEX-36 | Rheem | Electric | N/A | 0.99 | $500-$800 |
What You Will Actually Pay Installed
| Scenario | Rinnai Installed | Rheem Installed |
|---|---|---|
| Non-condensing gas, existing flue | $1,600-$2,400 | $1,200-$2,000 |
| Condensing gas, new PVC venting | $2,200-$3,500 | $1,800-$3,000 |
| Electric whole-home | $800-$1,800 | $700-$1,600 |
| Propane, new installation | $2,500-$4,000 | $2,000-$3,500 |
See our full water heater replacement cost guide for every line item. If you are replacing a tank heater, the tankless vs. tank 15-year ROI breakdown shows when the math works in your favor.
Warranty Comparison
| Coverage | Rinnai | Rheem |
|---|---|---|
| Heat Exchanger | 12 years | 12 years |
| Parts | 5 years | 5 years |
| Labor | 1 year | 1 year |
| Registration Required | Yes | Yes |
The warranties are identical on paper. Rinnai has a more established contractor service network in most markets. Register your unit within 30 days of installation.
Which Brand Should You Buy?
Buy Rinnai if: you have a large household (4+ people, 3+ bathrooms), live in a cold climate, need maximum flow rate (11.1 GPM), or long-term reliability matters more than upfront cost.
Buy Rheem if: you need same-day Home Depot availability, your plumber is more familiar with Rheem, you are on a tighter budget, or 9.5 GPM covers your demand. For a broader comparison of tankless brands, see the best tankless water heater roundup.
Tax Credits and Rebates
Condensing gas tankless units (UEF 0.82 or higher) qualify for the federal 25C tax credit through 2032: up to $600. Both brands qualify.
- Federal water heater tax credit 2026
- Utility rebates by state: $500-$3,000 available
- State-by-state rebate amounts
Rinnai vs. Rheem: FAQ
Is Rinnai better than Rheem?
For high-demand homes and cold climates, yes. For average-demand households, both at UEF 0.96 are functionally equivalent.
How long do these units last?
Both are rated for 20+ years with annual descaling. Real-world lifespan runs 15-20 years. See our tankless water heater maintenance tips.
Can I install one myself?
No. Gas appliance installation requires a licensed plumber in most states. Unpermitted installs void the warranty.
Which is easier to get parts for?
Rheem parts are more widely stocked. Rinnai often requires ordering through a distributor.
Do they qualify for the federal tax credit?
Yes. UEF 0.82 or higher qualifies for up to $600 under the 25C credit. See our tax credit guide.
Which brand has better recirculation?
Rinnai builds recirculation pumps into their RUR V-series. Rheem usually requires an external pump. If instant hot water matters, Rinnai wins.
Get Quotes Today
Both brands are solid. The right call depends on your household demand. See the best water heater buyer guide for the full tank vs. tankless decision tree.
