Rinnai Tankless Water Heater Sizing Calculator
Determine which Rinnai tankless water heater model is right for your home based on your hot water needs.
How to Choose the Right Rinnai Tankless Water Heater
Rinnai is a leading manufacturer of tankless water heaters, offering some of the most efficient and reliable models on the market. Proper sizing ensures your Rinnai unit delivers consistent hot water while maximizing energy savings. This guide focuses on selecting the ideal Rinnai model based on your household size, climate, and hot water usage patterns.
Rinnai's Tankless Product Lines
Rinnai offers several series of tankless water heaters, each with unique features:
High-Efficiency Condensing Models
- RUR Series: Indoor units with up to 96% efficiency (e.g., RUR199iN)
- RUC Series: Commercial-grade models with advanced controls
Non-Condensing Models
- V Series: Value-oriented models (e.g., V94IN)
- RL Series: Light commercial applications
Outdoor Models
- RU Model Line: Weather-resistant outdoor units
Key Sizing Factors for Rinnai Units
- Flow Rate (GPM): Rinnai models range from 5.3 to 11 GPM capacity
- Temperature Rise: Varies by model and groundwater temperature
- Gas Line Capacity: Higher BTU models require larger gas lines
- Venting Requirements: Condensing vs. non-condensing models differ
Rinnai Model Comparison Chart
| Model | Series | Max GPM | BTU | Efficiency | Bathrooms |
|---|---|---|---|---|---|
| RUR199iN | Condensing | 11.0 | 199,000 | 96% | 3-4 |
| RUR160iN | Condensing | 9.4 | 160,000 | 95% | 2-3 |
| V94IN | Value | 9.4 | 199,000 | 82% | 2-3 |
| V75IN | Value | 7.5 | 150,000 | 82% | 1-2 |
| RU199iN | Outdoor | 9.9 | 199,000 | 82% | 3-4 |
Climate Considerations
Rinnai provides climate-specific performance data for their models:
- Cold Climates: Require higher BTU models (RUR199iN recommended)
- Moderate Climates: Most Rinnai models perform well
- Warm Climates: Smaller units like V65EP adequate
Rinnai-Specific Features
- Circ-Logic: Advanced recirculation technology
- WiFi Connectivity: Control via Rinnai Control-R app
- Scale Detection: Alerts for maintenance needs
- Dual Heat Exchanger: In condensing models for maximum efficiency
- 12-Year Warranty: On heat exchangers for select models
Installation Requirements
Rinnai units have specific installation needs:
- Gas Line: ¾" minimum for most whole-house models
- Venting: PVC for condensing, stainless for non-condensing
- Clearances: Specific spacing requirements around unit
- Water Quality: Hard water may require treatment
- Professional Installation: Required for warranty
Frequently Asked Questions
What's the most popular Rinnai tankless water heater?
The RUR199iN is Rinnai's flagship model, offering 11 GPM capacity and 96% efficiency.
Can Rinnai units be installed outdoors?
Yes, the RU series is specifically designed for outdoor installation with freeze protection.
How does Rinnai compare to other brands?
Rinnai is known for superior build quality, advanced features, and industry-leading warranties.
Do Rinnai heaters work during power outages?
No, they require electricity for controls, but can work with battery backups.
What maintenance do Rinnai units require?
Annual flushing is recommended, especially in hard water areas.
Conclusion
Rinnai tankless water heaters offer exceptional performance when properly sized. Use our calculator above to identify which Rinnai models match your household's needs. For optimal results, consult with a Rinnai-certified installer who can assess your specific installation requirements and local code considerations.