Best High Efficiency Gas Water Heater 40 Gallon: Top Picks and Buying Guide
Choosing a high efficiency gas water heater can save energy, reduce bills, and ensure reliable hot water for busy homes. This guide highlights top 5 options that align with a 40-gallon capacity mindset, balancing efficiency, durability, and installation practicality. Explore product sections, a quick overview, and a detailed buying guide to compare features and performance.
Summary table of selected products:
| Product | Brand | Type | Highlights |
|---|---|---|---|
| A.O. Smith GCR-40LP ProMax Plus | AO Smith | Gas, 40 gal | Blue Diamond coating, self-powered gas valve, precise control |
| Rheem 50 Gal. Smart Hybrid | Rheem | Gas/Electric hybrid, 50 gal | Smart, high efficiency, requires dedicated circuit |
| Rheem Natural Gas Condensing Tankless | Rheem | Gas tankless | 0.4–9 GPM, condensing efficiency |
| Rheem 72-40-2 Electric 40 gal | Rheem | Electric, 40 gal | Rheemglas lining, insulation |
| APUS 190K BTU Outdoor Tankless | APUS | Gas tankless | 8.1 GPM, WiFi & remote control |
A.O. Smith GCR-40LP ProMax Plus High Efficiency Gas Water Heater, 40 gal
The GCR-40LP ProMax Plus combines high efficiency with durable construction. Its Blue Diamond glass coating provides superior corrosion resistance compared to standard glass lining, extending tank life in varied water conditions. A self-powered electronic gas valve uses a thermopile to generate the energy needed to operate the electronic gas control, eliminating reliance on external power. An internal microprocessor enhances operating parameters and tightens differentials for faster heating responses. This model targets households seeking reliable hot water with efficient fuel use and longer tank life.
Key features
- Blue Diamond glass coating for corrosion resistance
- Self-powered electronic gas valve with thermopile
- Internal microprocessor for precise sensing and faster heating
Rheem 50 Gal. Smart High Efficiency Hybrid Water Heater
This model blends high efficiency and smart features in a 50-gallon capacity, suited for households needing substantial hot water with minimal energy waste. It integrates with your home’s electrical system and typically requires a dedicated circuit, similar to larger electric appliances. While not a traditional solar-assisted unit, its hybrid approach optimizes energy use during peak demand periods. Installers should verify electrical wiring requirements and venting needs for safe, long-term operation.
Key considerations
- Electrical load and circuit requirements
- Hybrid operation balance between gas and electric elements
- Compatibility with existing venting and space constraints
Rheem Natural Gas Condensing Tankless Water Heater Indoor Up To 9 GPM
While not a 40-gallon tank, this condensing tankless unit delivers high efficiency for households seeking continuous hot water. With a flow rate of up to 9 GPM, it supports multiple fixtures simultaneously. The condensing design extracts more heat from exhaust gases, improving overall energy use. It includes electric ignition and is positioned for indoor installation in spaces with proper venting. Suitable for homes that want scalable hot water without a storage tank.
Key features
- Up to 9 GPM flow rate
- Condensing technology for higher efficiency
- Indoor installation with electric ignition
Rheem 72-40-2 240V / 4500W 40 Gallon Electric Water Heater
Although electric, this Rheem model is included for comparison within the same household water-heating ecosystem. It features a Rheemglas lined tank, R-Foam insulation, and an anode rod to protect against corrosion. The electric configuration provides a reliable alternative for homes where gas installation is impractical or where electric-only heating is preferred. This 40-gallon unit can be suitable for households with moderate hot water demand seeking improved efficiency over older electric tanks.
Rheem RTG-84XLN-3 High Efficiency Non-Condensing Outdoor Tankless Water Heater
This outdoor non-condensing tankless unit provides high efficiency and up to 8.4 GPM, suitable for households with multiple hot water needs. Its 180,000 BTU rating ensures rapid recovery during peak demand. Designed for outdoor installation with a durable metal cabinet, it supports easy wall mounting by a qualified installer. It offers flexibility for homes that want modern tankless performance without storage tanks.
Key considerations
- Outdoor installation suitability and venting
- GPM capacity for simultaneous hot water draws
- Electrical and gas supply requirements
Rheem RTG-70XLN-3 High Efficiency Non-Condensing Outdoor Tankless Natural Gas Water Heater
Another outdoor tankless option, this unit provides high efficiency with up to 7.0 GPM and a 160,000 BTU rating. It is designed for outdoor installation and supports straightforward wall mounting by a qualified installer. This model serves homes with moderate to high hot water needs, particularly where compact space and outdoor installation are advantageous.
Key considerations
- GPM capacity alignment with household demand
- Outdoor weather resilience and venting
- Professional installation requirements
APUS 190,000 BTU Outdoor Tankless Water Heater
This high-efficiency outdoor tankless water heater delivers 8.1 GPM and 190,000 BTU, supporting simultaneous showers and multiple outlets. Its compact outdoor-friendly design, WiFi and remote control capabilities, and direct 120V power connection enable easy integration with modern smart homes. It connects via standard 3/4 inch water and gas lines for broad compatibility.
Key considerations
- WiFi connectivity and app control
- GPM requirements for multi-outlet use
- Electrical and gas supply adequacy and safety
Buying Guide: Key Purchase Considerations for High Efficiency Gas Water Heaters
When evaluating high efficiency gas water heaters, consider capacity needs, type (tank vs. tankless), installation space, venting requirements, and energy savings features. Tank-style units excel at steady, ample hot water for family households, while tankless models offer on-demand efficiency and space savings. Condensing vs. non-condensing designs affect exhaust temperature, venting, and long-term energy performance. Compatibility with existing gas lines, electrical systems (where hybrids or electric components exist), and climate considerations also influence performance and cost of ownership.
Capacity and demand
- 40- to 50-gallon tanks suit typical family households with moderate hot water use.
- Tankless options scale to higher demand but may require larger gas lines and venting considerations.
Efficiency and operating costs
- Condensing systems recover more heat from exhaust gases, improving energy efficiency.
- Hybrid electric/gas systems can reduce energy consumption but require electrical infrastructure.
- Annual fuel utilization efficiency (AFUE) and energy factor metrics guide comparisons.
Installation and space
- Gas storage heaters require appropriate venting and clearance space.
- Outdoor tankless units demand weather protection and proper mounting.
- Electrical circuits and dedicated breakers may be needed for hybrid or electric components.
Reliability and maintenance
- Protect against corrosion with coatings or a robust anode system.
- Regular flushing and maintenance extend tank life for gas storage models.
- Consider warranty length and service availability in your region.
Cost and lifecycle considerations
- Initial installation costs versus long-term energy savings.
- Smart features and remote access may offer convenience but add upfront cost.
- Resale value and compatibility with home energy upgrades (like solar or heat pumps) may influence choice.