You may have heard of tankless water heaters. Since they do not need to hold heated water in reserve, no tank is required. Another term for this type of water heater is “demand-type” or “instantaneous water heaters.” As you might imagine from this terminology, tankless water heaters work only as needed, and consequently are more energy-efficient than traditional tank water heaters.
Here is how a tankless water heater works: When hot water is called for at a faucet or showerhead, cold water enters through a pipe into the tankless water heater unit. The water is then heated by a gas burner or an electric element.
The advantage is you no longer need to wait for a storage tank to fill up with enough hot water to deliver it to, say, your shower (which is why you sometimes suffer a cold shower even with the hot tap turned all the way on, particularly if you have family members using hot water all at the same time).
However, a tankless water heater’s output limits the flow rate to as little as two gallons per minute and not much more than five gallons a minute. Which basically means it is not an ideal application for large households, unless you are willing to consider installing multiple tankless water heaters.
The best application for tankless water heaters include:
- Small homes, apartments and condominium units intended for one or two occupants.
- Dedicated use for remote appliances, such as an outside bathroom or outdoor deck hot tub.
- A supplement to appliances such as dishwasher and clothes washing machines or a solar water heating system.
Which type is best for your home? Glad you asked, we covered that in a previous blog entitled, yes you guessed it, Which Type of Water Heater is Best for Your Home?
For this blog post we will cover five things you may not know about tankless water heaters:
- Is the hot water supply endless and instantly available?
- How energy-efficient are they?
- How long do they last?
- What are the required British Thermal Units (BTUs)?
- Do they require electricity? What about the gas-fired tankless water units?
1. Is Hot Water Instantly Available or Endless? And What’s the Difference?
One common misconception about tankless water heaters is that they provide hot water instantly. Some do, but some don’t. The ones that do employ a recirculation pump to provide hot water instantly.
However, all tankless water heaters supply hot water endlessly. As long as you have the hot water tap open, you’ll get hot water until you turn the tap off.
2. Are Tankless Water Heaters More Energy Efficient?
According to the Department of Energy, the average household spends between $400 to $600 on water heating each year. Water heating is the second largest household expense, accounting for 14 to 18 percent of your total utility bill.
Obviously, the more energy-efficient an appliance, the more potential savings on your utility bill. While actual cost savings depend on how the tankless water heater is used, on average, tankless water heaters are 96 to 98 percent efficient. That contrasts with a standard tank water heater unit that is typically at around 60 percent efficient.
Keep in mind that some tank water heaters are more energy-efficient than others due to better insulation and more efficient components. A high-efficiency tank water heater uses up to 8 percent less energy to do its job versus lower efficiency options.
Overall, though, tankless water heaters are still more energy efficient than standard tank water heaters.
The trade-off is that tankless water heaters cost more upfront than standard tank water heaters. However, over time you recoup that expense from lower energy costs. On average, a tankless water heater (if installed correctly) can save up to 30 percent off of heating costs because they only heat water when you’re using it.
3. What Is the Equipment Life of Tankless Water Heaters?
A tankless water heater has an operating lifespan of 20 to 30 years, depending on your water quality and if you perform required maintenance regularly. Compare that to the average 10 to 15 year lifespan of a standard tank water heater. This is largely because over time the tank eventually springs a leak and needs to be replaced. Obviously, this is not an issue for tankless water heaters.
Tankless water heaters do have to be cleaned periodically to ensure longevity. How often depends on how hard your water is (meaning how high the mineral content is in the water). If you have hard water, you should probably service the unit once a year. If you don’t have hard water or you use a water softener, you might go four to five years without any maintenance. Also bear in mind there are several electronic and moving parts that need to be serviced or replaced as needed in a tankless water heater.
Today’s water heaters in general are more efficient, safer and create fewer pollutants. This is important for your safety and the environment. There is a trade off, however. Newer water heaters require more regular maintenance because the devices built into them to make them safer and environmentally friendlier require regular cleaning and testing. Failure to do regular maintenance drastically reduces equipment lifespan.
Consult your plumbing professional for tankless water heater maintenance.
4. How Many BTUs Do Tankless Water Heaters Require?
Your first question is probably, what is a BTU? A British Thermal Unit is the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.
Gas-powered tankless water heaters require a dedicated appropriately sized gas pipe from the gas meter or liquid propane tank to the tankless water heater location. This requires a large amount of BTUs to operate. Generally speaking, the BTUs can range from 150,000-199,000 or more depending on the unit. In comparison, a standard 40 gallon tank water heater requires 38,000 BTUs.
Electric tankless water heaters are typically rated according to watts, which range from about 3.0kW to 36kW.
5. Do Tankless Water Heaters Require Electricity if They Are Gas-Powered?
In a word, yes. Electricity is still required even for a tankless water heater that operates on natural gas or liquid petroleum (LP). A 110-volt electrical outlet is required to power the gas tankless water heater unit’s control board, electronic ignitor and other parts.
Consequently, the downside to a tankless water heater is in the event of an electrical power outage, not only are your lights off, so is your tankless hot water heater unless you have a battery back-up or generator. In comparison, a standard tank water heater only requires gas to operate.
Ongaro & Sons Plumbing and Water Heater Services
Ongaro and Sons provides a full range of plumbing services, including water heater and tankless water heater repair and replacement. Our technicians are experienced certified plumbers who can quickly identify problems and fix exactly what is wrong. Ongaro and Sons’ technicians are knowledgeable in just about every kind of plumbing problem and how to resolve them. We specialize in water heater repair and replacement.
With the help of our plumbing professionals, you can be sure to select the right tankless water heater application that best suits your needs. We know a lot more about tankless water heaters than just these five things we’ve discussed. Because it is our job to know more, to provide our customers with the best service possible.
Our quality technicians are factory trained, so if your water heater breaks down, we have the expertise to repair any make and model. However, we recommend you avoid repairs and untimely breakdowns by taking advantage of our preventative maintenance programs.
Contact us with any questions about tankless water heaters. We’re happy to discuss your needs and deliver 100 percent customer satisfaction.