If you’re shopping for an LP gas tankless water heater, you want a model that delivers reliable hot water on demand, supports multiple fixtures, and fits your space. The following selections are among the best-suited options for American homes, chosen for capacity, efficiency, and practical use cases. Read on to compare which model is best for your household size, typical water demand, and installation needs. A quick buying table is provided below for a snapshot of key specs.
Quick Buying Snapshot
- Best for large homes with multiple showers: Ranein 8.5 GPM, 190,000 BTU
- Best compact option for 2–3 fixtures: APUS 140,000 BTU, 6.8 GPM
- Best mid-range for 2–4 fixtures: APUS 95,000 BTU, 4.42 GPM
- Best outdoor installation option: Rheem RTG Series 7.0 GPM
- Best balance of capacity and control: APUS 140,000 BTU with Wi‑Fi and booster
Summary table of selected products:
| Product | GPM | BTU | Best For | |
|---|---|---|---|---|
| Ranein Propane 8.5 GPM | 8.5 | 190,000 | Large homes, multiple bathrooms | High flow; may require larger venting |
| APUS 140,000 BTU | 6.8 | 140,000 | Whole-home with 2 showers | Booster pump option; Wi‑Fi app |
| APUS 95,000 BTU | 4.42 | 95,000 | 2–3 fixtures; compact space | Low-flow start tech; precise temperature |
| Rheem RTG Outdoor 7.0 | 7.0 | 160,000 | Outdoor installation, multi bathroom | Outdoor venting; large capacity |
| APUS 140,000 BTU with Wi‑Fi | 6.8 | 140,000 | Whole home, smart controls | Zero cold-water tech; app control |
Ranein Propane, 4.3 GPM, 100,000 BTU
Best for compact spaces and smaller homes needing dependable on-demand hot water for 3–4 points of use. This model provides 100,000 BTU with a 4.3 GPM flow and four preset modes to match seasonal needs and room use. Temperature is adjustable from 95°F to 155°F with a high-temperature lock for safety. It is designed for indoor installation and supports anti-freeze protection in cold climates. Choose this if you want straightforward operation with clear presets and strong efficiency for moderate demand.
- Best for: small to midsize homes with up to 4 fixtures
- Why selected: strong balance of flow, temperature control, and safety features
- Caution: 100,000 BTU may limit performance at very high simultaneous demand in larger homes
APUS Propane, 95,000 BTU, 4.42 GPM
Best for two showers plus a sink, delivering precise temperature control and stable performance. This unit uses 95,000 BTU with a 4.42 GPM capacity, featuring precise sensors and smart CPU control to keep temperatures within a narrow tolerance. It emphasizes energy efficiency with a claimed high efficiency rating and anti-freeze protection. Choose this if you want reliable temperature stability at a moderate price point and a compact footprint.
- Best for: mid-sized homes with steady hot water needs
- Why selected: precise temperature control; good energy efficiency
- Caution: may require careful venting planning for indoor installation
Rheem RTG Outdoor 7.0 GPM
Best for large homes or households with multiple showers that require continuous hot water outdoors. This 7.0 GPM outdoor unit delivers about 160,000 BTU and is designed for outdoor installation, avoiding indoor venting challenges. The model emphasizes energy efficiency with a non-condensing design and supports multiple simultaneous fixtures. Choose this if you want outdoor placement and high flow, especially in homes with many bathrooms.
- Best for: large homes and outdoor installation
- Why selected: high flow and outdoor venting flexibility
- Caution: outdoor exposure requires protection from weather and proper clearance
Ranein Propane, 8.5 GPM, 190,000 BTU
Best for large homes with high simultaneous water demand, such as households with multiple bathrooms and long hot-water runs. This 8.5 GPM model provides 190,000 BTU for robust performance and features like anti-freeze protection and LED indicators. It’s designed for indoor use with wall mounting. Choose this if you need top-end flow to support several fixtures at once and want a heater that maintains temperature under heavy use.
- Best for: large homes with many simultaneous hot-water needs
- Why selected: strongest flow among the listed models
- Caution: higher BTU may require careful venting and local code compliance
Buying Guide: Key Considerations For LP Gas Tankless Heaters
Capacity and demand: Match GPM and BTU to your typical hot-water usage. Larger homes with several bathrooms may benefit from high-flow units (6–8 GPM, 140,000–190,000 BTU). Smaller homes or apartments can be comfortable with 4–6 GPM and 95,000–140,000 BTU.
Installation location: Indoor models save space but require venting and proper clearance. Outdoor units avoid venting but need weather protection and freezing considerations. Consider local climate when choosing anti-freeze features and insulation.
Temperature control: Precision temperature control helps prevent scalding and ensures comfort for multiple fixtures. Look for models with narrow setpoint ranges and high-accuracy sensors.
Energy efficiency: A higher UEF and efficient heat exchangers reduce energy usage. This matters more in homes with frequent hot-water use or high simultaneous demand.
Smart features and ease of use: Some units offer Wi‑Fi apps, programmable presets, and quick-start technologies. These can simplify operation and improve comfort for households with variable schedules.
Maintenance and reliability: Consider installation accessibility, ease of service, and brand support. Regular maintenance reduces the risk of cold-water shocks and ensures longevity in propane systems.
FAQ
- What size tankless LP gas heater do I need for a 2-bath home?
A heater in the 4–6 GPM range (roughly 95,000–140,000 BTU) is generally suitable for two bathrooms, depending on shower usage and sink demand. - Can I install an LP tankless heater indoors?
Yes, but ensure proper venting, clearance, and compliance with local codes. Indoor models require safe venting and adequate combustion air. - Is higher BTU always better?
Not necessarily. Higher BTU provides more flow, but you must match it to your home’s water draw and venting capabilities to avoid waste and improper venting. - Do LP tankless heaters save energy?
Yes, by delivering hot water on demand, they avoid standby losses associated with storage tanks. Efficiency depends on unit design and usage patterns. - What maintenance is required?
Routine checks for venting, cleaning heat exchangers if needed, and inspecting gas lines and connections help maintain performance and safety. - Can I connect multiple fixtures to a single tankless unit?
Yes, many models support 2–6 fixtures simultaneously. Check the GPM rating to ensure sufficient hot water for all fixtures.