58 Gallon Water Heaters - Your Complete Efficiency Guide

When it comes to residential water heaters, the 58 gallon capacity offers an excellent combination of storage volume and recovery rate for many homes. With the right design and features, 58 gallon models can deliver an abundant supply of hot water in an energy efficient package.

How 58 Gallon Water Heaters Work

Like most residential units, 58 gallon water heaters operate on a straightforward process. Cold water enters the tank where it surrounds a heat exchanger containing hot combustion gases from the burner. This heats the water to the desired set temperature. The now hot water exits the tank through the hot water outlet and flows to fixtures when needed. Once hot water is drawn, the burner activates again to reheat the tank and maintain the set temperature. Most 58 gallon models are fueled by natural gas or propane and vent using atmospheric venting.

Key Components

Some of the key components that make a 58 gallon gas water heater operate efficiently include:

• Burner - Heats the air and produces hot combustion gases that transfer heat to the water.
• Heat exchanger - Transfers heat from the burner to the water.
• Thermostat - Monitors water temperature and signals the burner when to activate.
• Insulation - Reduces standby heat loss from the tank.
• Anode rod - Protects against corrosion.

Key Specifications

Water Heater Capacity

While 58 gallon water heaters have a stated capacity of 58 gallons, the actual usable hot water volume is typically lower - closer to 50-55 gallons. This is because capacity measures only the tank size, not the amount of hot water that can be delivered. Factors like heater orientation and plumbing configurations affect usable capacity.

First Hour Rating

An important performance metric is the first hour rating - the amount of hot water the heater can supply per hour, starting with a full tank. Many 58 gallon models have first hour ratings around 65-90 gallons. The higher the rating, the more hot water is available during peak demand.

Recovery Rate

Recovery rate, stated in gallons per hour (GPH), is the rate at which a water heater reheats and replenishes its supply of hot water after it's been depleted. Most 58 gallon units have recovery rates between 50-65 GPH. Factors like burner strength and insulation impact recovery rate.

Energy Efficiency

Energy factor (EF) was previously used to rate gas water heater efficiency. Today, the Uniform Energy Factor (UEF) is the recognized metric. The higher the UEF, the more efficient the heater. Typical UEF ratings for 58 gallon heaters range from 0.50 to 0.70.

Efficiency Compared to Other Sizes

When it comes to energy efficiency, bigger isn't always better. Larger tanks have more surface area, increasing heat loss. Compared to 50 gallon models, 58 gallon heaters are slightly less efficient with UEF ratings around 0.63 vs. 0.65. However, they're more efficient than larger 75-80 gallon units with lower UEFs around 0.57.

Features That Improve Efficiency

Beyond tank size, certain features directly impact energy efficiency:

Burner Design

Special burner designs like low-NOx and blue flame burners increase combustion efficiency, resulting in higher EF ratings.

Insulation

Most models today use foam insulation rather than traditional fiberglass. Foam provides better insulation, with 2-3" thickness optimal for reducing standby losses.

Electronic Ignition

Electronic ignition eliminates the need for a standing pilot light, improving efficiency by 2-5%.

Heat Traps

Factory installed heat traps on the cold water inlet and hot water outlet prevent convection heat loss through the pipes.

Installation Considerations

Proper installation is key to maximize efficiency and get the most out of your 58 gallon water heater. Some important factors include:

• Location - situate close to high demand areas.
• Venting - follow vent manufacturer guidelines.
• Gas line sizing - confirmed by installer.
• Electrical - 120V connection with 15A breaker.
• Professional install - recommended for code compliance, safety.

Ongoing Maintenance

To keep your 58 gallon water heater running efficiently for years to come, follow these maintenance practices:

• Drain and flush annually to remove sediment.
• Inspect anode rod every 2-3 years and replace as needed.
• Keep exterior clean by wiping down periodically.
• Visually inspect burner flames for proper appearance.
• Check T&P valve annually by running water through it.

Environmental Impact

For eco-friendly operation, look for models certified as ENERGY STAR Most Efficient with UEF over 0.67. The enhanced insulation reduces heat loss and carbon emissions. Also select low-NOx certified models emitting 50-75% less nitrogen oxides.

Cost Effectiveness

The higher initial cost of energy efficient models pays off over time through savings of up to $100 annually on utility bills for gas. Plus, federal tax credits and local utility rebates can defray upfront costs. Professional installation optimizes efficiency and may be required for rebates.

Comparing Top Models

Two of the top rated 58 gallon gas water heaters are:

Rheem G100-58

With up to $1300 in potential savings over 10 years and a 90 gallon first hour rating, the Rheem G100-58 is a solid mid-range choice combining value and efficiency.

As a hybrid heat pump model, the Rinnai 58 gallon improves efficiency by up to 40%. It achieves the highest energy factor ratings in its class.

When shopping for a new 58 gallon gas water heater, be sure to consult this guide to make the most informed decision for efficiency, performance, and savings.