Eternal Water Heaters
Eternal manufactures hybrid condensing water heaters that pair a high-efficiency condensing burner with a small stainless steel buffer tank. This hybrid approach delivers instant hot water, eliminates cold-water sandwich, and achieves up to 0.96 UEF efficiency. Models are available in natural gas and propane configurations for residential and light commercial use.
Eternal Water Heaters Product Lines
Certifications & Standards
Water Heaters How-To Guides
View All →How to Adjust Water Temperature
Set your gas or electric water heater thermostat to the right temperature for comfort, safety, and lower energy bills -- plus how to verify the actual output with a thermometer.
How to Choose the Right Size Water Heater
Calculate the right water heater size so you never run out of hot water -- covers first-hour rating for tanks, GPM for tankless, quick sizing charts, and the mistakes that leave people taking cold showers.
How to Flush Your Water Heater
Flush sediment from your tank water heater to cut energy bills, eliminate rumbling noises, and add years to its life -- the most important maintenance task most homeowners skip.
Common Water Heaters Problems
View All →Leaking Water Heater
Water around the base demands immediate attention -- floor damage, mold, electrical hazards. Could be loose fittings, a failing T&P valve, a bad drain valve, or a rusted-through tank that needs replacement.
No Hot Water
No hot water from any fixture? Cause depends on gas vs. electric. Common culprits: pilot light out, tripped breaker, failed element, faulty thermostat or gas valve.
Pilot Light Won't Stay Lit
Lights but will not stay lit? Almost always the thermocouple -- a safety sensor that detects the pilot flame. When it fails, the gas valve shuts off. Straightforward DIY repair, under $25.