Unless you have a household of 5+ people, multiple high-flow showers running simultaneously, or a large soaking tub, you probably don’t need an 80-gallon water heater. For most standard homes, a 40- to 50-gallon tank or an on-demand tankless system is sufficient.
Traditional 80-gallon water heaters have been phased out due to strict federal energy efficiency regulations enacted by the Department of Energy (DOE). Standard electric models larger than 50-55 gallons are largely unavailable because they can no longer meet the required Energy Factor (EF) ratings.
Water Heater Size
30-gallon tank: ~5–7 minutes of hot water. 40-gallon tank: ~8–10 minutes. 50-gallon tank: ~10–12 minutes. 80-gallon tank: ~15–20 minutes.
To prevent Legionella bacteria (which causes Legionnaires' disease) from multiplying, your water heater should be set to 140°F (60°C). However, because water at this temperature poses a severe scalding risk, it must be mixed with cold water using a Thermostatic Mixing Valve (TMV) to deliver safe, warm water to your taps.
Naturally, tanks that heat more gallons of water typically have a higher price point, so the larger the tank size, the more you can expect to pay. For example, the average 40-gallon water heater installation cost runs between $1,000 and $2,500, while its 80-gallon counterpart runs between $2,650 and $3,910.
Yes, 80-gallon water heaters are still manufactured, but their availability depends on the type of unit you need.
The Home Depot offers traditional water heater tanks and modern tankless units, both powered by either gas or electricity. Depending on your selection, the average cost for standard tank installation is generally between $1,600 to $2,400. Tankless installation can range from $2,400 to $5,400.
The first signs of Legionnaires’ disease typically appear 2 to 14 days after exposure to Legionella bacteria. Early symptoms are often flu-like and include:
Between 77∘F and 113∘F (25∘C to 45∘C), Legionella bacteria thrive and multiply.
The 4-minute shower rule is a sustainability and cost-saving initiative advising people to limit their daily showers to four minutes or less. This practice helps conserve water, reduce energy used for heating, and lower household utility bills by limiting consumption to approximately 36–40 liters (roughly 9.6–10.5 gallons) per shower.
If a standard showerhead is fitted, it will use around an extra half a gallon each minute, accounting for a 25-gallon emittance every 10 minutes, or 50 gallons throughout a 20-minute shower. *1 gallon = 4.54 litres.
Water Heater Capacity: Traditional tank water heaters have a fixed capacity, typically ranging from 30 to 80 gallons. If your household takes multiple long showers in quick succession, you might deplete the hot water supply, causing the water heater to work harder to heat additional water.
In summary, an 80-gallon water heater is likely a good fit if you have a large household (5+ people), multiple bathrooms, frequent simultaneous hot water use, or high-demand fixtures. However, if your household is smaller and your peak demand is lower, a smaller tank is the more energy-efficient and cost-effective.
This problem usually comes down to capacity, heat production, or mixing issues inside your plumbing system. Sometimes the fix is simple, like adjusting your water heater temperature or flushing out sediment. Other times you may need a new mixing valve, an element replacement, or a different size water heater.
The most reliable water heater brands generally include A.O. Smith, Rheem, and Bradford White for traditional tanks, and Navien or Rinnai for tankless models. These brands consistently rank highest among plumbers and consumer reviews for durability, parts availability, and long-term performance.
A 10-minute shower typically uses 20 to 25 gallons of hot water. Because showers are usually mixed with cold and hot water to reach a comfortable temperature, the actual volume of hot water drawn from your heater will usually be slightly less, while a low-flow showerhead can reduce this amount by up to 50%.
A: Traditional tank water heaters usually last 8–12 years, while tankless units often last 15–20+ years. Q: Should I replace my water heater if it's over 10 years old? A: Often yes. Even if it still works, the risk of leaks and sudden failure increases significantly after 10 years.
Excessive Water Pressure: High pressure stresses your system and shortens its lifespan. A pressure-reducing valve can help. Undersized System: A unit that's too small for your household's demand works harder and wears out faster. Proper sizing during installation is critical.
Legionnaires' disease is usually contracted by breathing in small, contaminated water droplets (mist or aerosol) that contain Legionella bacteria. It is not spread person-to-person.
Legionella bacteria are killed through specific physical and chemical methods, primarily focusing on extreme temperatures and strong disinfectants.
Most healthy people exposed to Legionella don't get sick. However, certain factors can put people at increased risk for getting Legionnaires' disease: 50 years of age or older. Having a chronic lung disease, such as Chronic Obstructive Pulmonary Disorder (COPD), or emphysema.
Stores like Home Depot and Lowe's often include removal when delivering a replacement unit. This is the most convenient option, especially if the old unit is still in place and connected.
Drawbacks of Tankless Water Heaters
As discussed above, the biggest downside of owning a tankless water heater is its higher cost. The initial installation and unit costs are more expensive than a traditional storage-tank water heater.
Yes, Costco sells water heaters, including traditional tank and tankless models (mostly from the brand Rheem). Rather than picking one up off the shelf, you purchase the unit and schedule a home consultation through their affiliated local contractors.