Looking for an efficient condensing tankless water heater that fits your home and fuel type? This guide highlights top models designed to deliver reliable hot water while saving energy. Ideal buyers: new homes needing whole‑home hot water, multi‑bath households seeking rapid recovery, and homeowners upgrading from non‑condensing units. The table below compares five standout options to help you choose quickly.
| Product | GPM | BTU | Fuel | Best For |
|---|---|---|---|---|
| Rinnai RX199iN | Up to 11.1 | 199,000 | Natural Gas or Propane | Large homes needing multiple simultaneous hot water uses |
| Rinnai RXP199iN | Up to 11.1 | 199,000 | Natural Gas or Propane | Indoor/Outdoor versatility with built‑in recovery features |
| Rinnai RX160iN | Up to 9 | 160,000 | Natural Gas or Propane | Medium to large homes with versatile installation |
| ThermoMate CZ480NG | 5.28 | 114,000 | Natural Gas | Two showers simultaneously in mid‑sized homes |
| Westinghouse Smart Tankless | 7.9 | 180,000 | Natural Gas | Whole‑home use with WiFi control |
Rinnai RX199iN Condensing Tankless Water Heater
The RX199iN is a compact, dual‑fuel capable unit designed for indoor or outdoor use with Versa Vent. It supports up to 11.1 GPM and 199,000 BTU, suitable for larger households needing multiple simultaneous hot water draws. Its Smart Sense gas control enables propane or natural gas operation, and a Quick Flush feature simplifies maintenance. Best for: homes with higher hot water demand or when outdoor placement is needed. Caution: outdoor installation requires the RX-OVC vent cap and proper venting compatibility.
Rinnai RXP199iN Smart Sense Condensing Tankless Water Heater
This model mirrors the RX199iN in capacity and installation flexibility but emphasizes built‑in WiFi control compatibility and enhanced control features. It delivers up to 11.1 GPM with a compact footprint, making it ideal for homes needing strong performance in a smaller space. Best for: tech‑savvy buyers who want remote monitoring and control. Caution: WiFi module is separate (not included), which may affect initial setup plans.
Rinnai RX160iN Condensing Smart Sense
The RX160iN provides up to 9 GPM with 160,000 BTU and similar Versa Vent installation flexibility for indoor or outdoor use. It’s a solid pick for medium‑to‑large homes that don’t need the maximum GPM but still require reliable, continuous hot water. Best for: households balancing space constraints with a solid flow rate. Caution: slightly lower GPM cap than the flagship RX199iN models.
ThermoMate CZ480NG Condensing Tankless Water Heater
The CZ480NG is a compact condensing unit with 5.28 GPM capacity and 114,000 BTU. It uses a dual heat exchanger—one stainless steel condensing path and an oxygen‑free copper heat exchanger—to enhance heat recovery. Best for: homes with moderate hot water needs or where a smaller unit is required. Caution: 5.28 GPM may limit simultaneous uses in busier households.
Westinghouse Smart Tankless Water Heater
Westinghouse offers a whole‑home solution with 7.9 GPM and 180,000 BTU, featuring WiFi app control for temperature management and monitoring. Best for: households that want remote operation and clear temperature stability (+/−1°F). A caution: data notes non‑condensing operation in some models; verify venting and installation specifics for your climate.
Buying Guide
Key considerations when choosing a condensing tankless heater:
- GPM needs: Match the unit’s maximum flow to your household’s peak hot water draw. Larger homes may require 9–11 GPM units.
- Fuel type and venting: Ensure your home has the appropriate natural gas or propane supply and compliant venting for outdoor versus indoor installation.
- Installation flexibility: Indoor/outdoor capability and Versa Vent compatibility affect placement options and retrofit costs.
- Energy efficiency: Condensing designs offer high efficiency (UEF ratings around 0.97–0.98). Higher efficiency can reduce energy use, especially in cold climates.
- Controls and connectivity: WiFi modules and app controls aid in monitoring and maintenance but may be sold separately; plan for integration with existing smart home setups.
- Maintenance features: Quick Flush and service access simplify annual maintenance, protecting long‑term performance.
- Safety protections: Look for frost protection, flame failure detection, dry‑fire protection, and automatic shutdown to reduce risk in varying climates.
- Warranty and service availability: Local support and part availability can influence long‑term reliability beyond initial purchase.
FAQ
- What does “condensing” mean in tankless water heaters?
It refers to capturing and reusing exhaust heat to improve efficiency, typically yielding higher energy savings. - Which unit is best for a large family with multiple bathrooms?
The RX199iN and RXP199iN offer higher flow up to 11.1 GPM, ideal for busier households. - Can I install a condensing tankless heater outdoors?
Yes, but check venting requirements and use the correct outdoor vent cap (RX‑OVC when applicable). - Do all these models require a wifi module for smart features?
Some have built‑in control with optional wifi modules; confirm with the specific model and retailer. - Is 5.28 GPM enough for two showers?
It can be, depending on inlet water temperature and desired shower temperature; higher GPM units provide more flexibility.