Whether you’re building a new home or replacing an old water heater, you’ll need to choose between a storage tank water heater and a tankless model. Each option has its own advantages and drawbacks, so it’s essential to weigh your needs before you make a decision.
What Are Storage Tank Water Heaters?
First introduced in 1889, storage tank water heaters heat water and store it for use when needed. Today’s models are more energy-efficient and durable than those made even just 10 years ago, helping homeowners save on both energy bills and replacement costs.
How It Works
Storage tank water heaters work by heating and storing a set amount of water for use when needed. When cold water enters the tank, a flame or heating element heats it, causing the water to rise to the top due to the principle of convection. Hot water, being less dense, naturally rises while cooler water stays at the bottom. The outlet pipe at the top of the tank then directs the hottest water to your faucet, showerhead, or appliance. As the hot water is used, the tank refills with cold water from the bottom, and the heating process begins again, ensuring a continuous hot water supply.
Types
Storage tank water heaters can run on various fuel types, including natural gas, propane, and electricity. Natural gas models are popular because they tend to be the cheapest to operate. Electric heaters have a lower upfront cost but are typically more expensive to run.
Advantages
Storage tank water heaters are a great choice for large households because they can supply a significant volume of hot water when needed. With sizes ranging from 40 to 120 gallons, they handle high-demand situations, such as several people taking showers during the morning rush before work or school. This ensures that everyone has access to hot water without worrying about running out, making it an ideal solution for families with multiple members needing hot water at the same time.
Additionally, traditional water heaters are generally more affordable than on-demand models. If you already have a conventional water heater, replacing it with another is also simpler than switching to a tankless heater, which can require more extensive modifications.
Drawbacks
One of the main drawbacks of storage tank water heaters is their limited hot water supply. If your tank isn’t large enough to meet demand during high-use times, you may have to wait for the unit to heat more water. This process can take anywhere from 30 minutes to over an hour, depending on the tank’s size and the incoming water’s temperature.
Traditional heaters also waste energy because they continuously maintain the water temperature, even when you’re not using it. This constant heating can result in higher energy bills. Additionally, storage tank heaters take up a significant amount of space, making them difficult to fit in smaller homes or apartments.
What Are Tankless Water Heaters?
Instead of holding water in a tank, on-demand water heaters generate hot water whenever you need it. This design is more efficient than traditional tanked water heaters.
How It Works
When a hot water tap is turned on, cold water enters the unit and passes through a heat exchanger, where either a gas burner or an electric element rapidly raises its temperature. The heated water then flows directly to the open tap or appliance, eliminating the need for a storage tank.
The system activates instantly when hot water is called for, using a built-in flow sensor to detect water movement. Once the sensor detects flow, it signals the heating element or burner to ignite, rapidly warming the water as it moves through the exchanger. When the tap is closed, the sensor detects the drop in flow and shuts off the heating mechanism, ensuring energy is only used when needed. Each unit has a specific flow rate, measured in gallons per minute (GPM), which determines how much hot water it can deliver at once.
Types
Tankless water heaters come in two main types: whole-house and point-of-use models. Whole-house tankless water heaters are designed to provide hot water to multiple fixtures and appliances at the same time. These units are installed centrally and deliver hot water on demand throughout the home, making them an excellent choice for households looking to replace a traditional storage tank system.
In contrast, point-of-use water heaters are compact units that heat water for a single fixture or appliance, such as a kitchen sink, bathroom faucet, or dishwasher. They are often installed in areas far from the main water heater to reduce the wait time for hot water. In larger homes, point-of-use heaters can supplement a whole-house system to improve efficiency and convenience.
When comparing on-demand gas water heaters, condensing models offer greater efficiency. Non-condensing versions vent hot exhaust gases outside, while condensing models capture and reuse heat from those gases in a second heat exchanger. This process increases energy efficiency, reducing heat loss and lowering operating costs.
Advantages
Tankless water heaters offer several key advantages for homeowners, particularly in terms of size, efficiency, and convenience. Their compact design allows them to fit into smaller spaces, which is especially beneficial for homes with limited room for larger units. Unlike traditional storage tank water heaters, which continuously heat and store a large volume of water, tankless heaters only heat water when it’s needed, eliminating the ongoing energy waste associated with keeping a tank of water hot 24/7.
Another advantage is their lower maintenance requirements. Tankless water heaters have fewer components than traditional models, making them more straightforward to operate and maintain. While regular tune-ups are still recommended to ensure the unit functions at its best, they require less upkeep than traditional systems.
Additionally, tankless water heaters provide an endless hot water supply as long as the demand stays within the unit’s capacity. You won’t need to cut a shower short to ensure there’s enough hot water for the next family member, making them ideal for busy households. However, it’s important to select a unit with an adequate flow rate to meet your household’s needs.
Drawbacks
While tankless water heaters offer several benefits, they also have some drawbacks. One of the main challenges is their higher upfront cost. Tankless units are typically more expensive to purchase and install than traditional storage tank models. Additionally, if you have a large household, you may need to install multiple units to meet the demand, which can further increase costs.
The issue is that tankless water heaters have a flow rate limit. A unit with a lower flow rate might struggle to meet demand if your household requires a high volume of hot water, such as running the dishwasher and doing laundry simultaneously. This could result in reduced water temperature or pressure, disrupting your daily routine.
Contact Your Local Professionals
At Summit Heating, A/C, Plumbing & Electrical, we have been serving the residents of Denver, CO and the surrounding areas since 1998. We install, maintain, and repair all types of water heaters. You can also count on us for your other plumbing needs, including drain cleaning, pipe repair, and leak detection services. Contact us today to schedule an appointment with one of our experienced team members.
