You can't run out of hot water with tankless water heaters – unless, of course, the power supply is off or goes out. However, a tankless water heater can have trouble keeping up with demand if too many things require hot water all at once.
Yes, you can :run out: of hot water with a tankless water heater.
The Heating Process of a Tankless System
A heat exchanger swiftly moves heat from gas jets to the water moving through the pipes: it's a fast process and the water heater can just keep doing it and sending out hot water. There's no supply that will get drained and a long process afterwards to heat up more.
A tankless water heater cannot provide hot water faster than its ability to heat the water. While a tank unit can provide hot water for multiple uses at once, a tankless unit might not be able to support simultaneous usage, such as washing dishes, taking a shower and running a washing machine all at once.
Tankless water heaters are able to provide endless hot water because they heat your water on-demand instead of from a tank (which can eventually run out of hot water). After the demand for hot water has been fulfilled, the water heater turns off and the heat exchanger cools back down.
Although your tankless unit is designed to provide hot water on demand, it has a specific capacity. You can potentially exceed this capacity by running too many faucets or showers at one time. As a result, you can end up with a cold shower.
More expensive installation and maintenance.
Tankless systems require special venting, rerouted gas lines, possibly multiple units for a larger household, and sometimes maintenance like installing a softener.
Additional Installation Costs
Tankless water heaters are much more complex than traditional hot water tanks. As a result, they require professional installation. If you're switching from a hot water tank to a tankless unit, you will likely need your gas lines rerouted, as well as a larger gas supply line.
Absolutely! In fact, tankless water heaters are becoming the standard for new home construction because of the energy efficiency.
Because tankless water heaters only consume energy when you need hot water, they're more energy efficient, saving you money on water and energy bills.
With a tankless water heater, you can take a shower, use the dishwasher, and do laundry all at the same time without losing hot water.
The federal tax credit for tankless water heaters in 2024 is an excellent opportunity for homeowners to save money while investing in energy-efficient water heating solutions. This tax credit is effective from January 1, 2023, to December 31, 2032.
Tankless water heaters usually last for around 15-20 years before they need to be replaced, but they may need replacing sooner if they start to break down or lose efficiency. Some common signs your tankless water heater needs to be replaced include: Low water pressure. Water doesn't get hot.
Electric Tankless Water Heaters
They're less expensive than gas-powered ones but aren't efficient if you run multiple hot water devices. They may struggle to keep up with multiple appliances at the same time.
You don't need to wait for a storage tank to fill up with enough hot water. However, a tankless water heater's output limits the flow rate. Typically, tankless water heaters provide hot water at a rate of 2–5 gallons (7.6–15.2 liters) per minute.
Inefficient heating due to temperature: The efficiency of a tankless water heater may decrease with the incoming water is too cold. Consider preheating the cold water to alleviate stress on the heater. Inspect built-in freeze protection system: Most tankless water heaters come with a built-in freeze protection system.
Even for homes with high water usage, up to 85 gallons per day, tankless water heaters can offer up to 14% energy efficiency savings. However, while they offer energy savings, the higher upfront costs and installation expenses can result in a long payback period, ranging from 12 to 27 years.
A 50-gallon water heater should be replaced with a tankless system with a 10 GPM flow rate just to be safe. Selecting the right flow rate ensures you won't experience cold showers or excessive energy costs. Proper sizing optimizes performance, providing hot water on demand without unnecessary waste.
But on average, different family sizes require the following sizes of tankless water heaters: Family of 2 — 6-8 GPM. Family of 3 — 7-9 GPM. Family of 4 — 8-10 GPM.
Unlike traditional storage water heaters, tankless units may not be able to meet your home's hot water needs if you have multiple outlets running simultaneously. This is because the flow rate of a tankless unit may not be high enough to support multiple uses of hot water at the same time.
Electric tankless water heaters still save homeowners around $44 per year according to the US Department of Energy. Longer useful lives than storage tank water heaters. Tankless water heaters typically last 20 to 30 years, double the forecasted useful life of a storage tank water heater.
You can't run out of hot water with tankless water heaters – unless, of course, the power supply is off or goes out. However, a tankless water heater can have trouble keeping up with demand if too many things require hot water all at once.
Smaller heaters can't supply multiple hot water applications at once. Need for multiple units. Some tankless hot water heaters service an entire home, but the flow rate may limit effectiveness in large, busy households. It may be necessary to buy smaller water heaters for each hot water tap.
High Purchase and Installation Costs: The price of a tankless water heater can be a restrictive factor. Installing a tank-style water heater typically costs about $900, while the average cost to install a tankless water heater can exceed $3,000.