The unit heats the water as long as this is open. When it is closed, the tankless unit stops heating the water. It is true that tankless water heaters do not require a lot of space. A large unit requires an area no larger than 24 inches square and ex- tends from the wall by about 8 to 10 inches.

What are the power requirements for a tankless water heater?

Most tankless gas water heaters require a 15 ampere or 20-ampere 120-volt circuit to power the electric pilot light and the control board. The National Electrical Code requires instantaneous water heaters to have circuits not exceeding 120 amperes and protected at not more than 150 amperes.

What is the downside of a tankless water heater?





The main disadvantage of tankless water heaters is their upfront cost (unit and installation) is significantly higher than tank-style heaters. Including installation, tankless water heaters cost 3 times more than tank-style water heaters on average.

Can you install a tankless water heater anywhere?

Tankless water heaters can be installed anywhere inside your home. You can even have a tankless water heater in a bathroom! Some families with larger homes choose to install two, one for each floor, for example. Because of their small size, they fit in closets, cabinets, pantries or laundry rooms.

What two requirements are necessary to size a tankless water heater?

There are two factors that need to be considered when sizing a tankless water heater:

  • Flow Rate (GPM): How much hot water you will need at any given time.
  • Temperature Rise (ΔT): The difference between the incoming cold water temperature and the desired temperature.

Does a tankless water heater need its own breaker?





A tankless water heater will require a dedicated circuit as specified by the installation manual of the unit that has been selected. If you need additional space in the panel for the circuit breaker then a quad circuit breaker may be allowed as specified by the make and model of the panel.

Does a tankless water heater require a GFCI outlet?

Most tankless water heaters are placed outdoors. The attachment plug serves as the disconnect and the receptacle shall be protected by GFCI. If there’s a new circuit that serves only exterior receptacles, no AFCI is required. If the receptacle is added to a circuit, there’s most likely a requirement for AFCI.

Can I replace my hot water heater with a tankless?

Absolutely! In fact, tankless water heaters are becoming the standard for new home construction because of the energy efficiency. Newer tank water heaters have a UEF (Uniform Energy Factor) rating of 0.70 compared to your standard tankless water heater that has a rating of 0.94.

Is it worth switching to a tankless water heater?

Tankless: Gas and electric tankless water heaters run more efficiently than the conventional water heaters of the same fuel type. We rated the annual energy consumption cost Excellent for a gas model but only Fair for an electric, but both rate Very Good for energy efficiency.

Can a tankless water heater flood a house?



But because tankless water heaters don’t actually store water at all, the risk of flooding is tremendously reduced (although damaged pipes still pose a potential risk).

How many gpm do I need for my house?

The average household needs 100 to 120 gallons per person per day, and a flow rate of about 6 to 12 gallons per minute.

How many gpm do I need for tankless water heater?

Consider how many of these needs you may have simultaneously to determine the maximum flow rate you require. For a home with 1 bathroom, we recommend 6-7 GPM; 2 bathrooms, 8 – 9 GPM; and 3+ bathrooms, 9-11 GPM.

Dishwasher 0.5 – 1.0 GPM
Bath tub 2.5 – .0 GPM
Jacuzzi/Hot tub 4.0 – 5.0 GPM

How big of a tankless water heater do I need for a family of 4?



What Size Tankless Water Heater Do I Need For A Family Of 2, 3, 4, 5, Or 6?

Number Of Family Members: Gas Tankless Heater Size (GPM) Electric Tankless Heater Size (kW)
What size tankless water heater do I need for a family of 3? 7-9 GPM 15-23 kW
What size tankless water heater do I need for a family of 4? 8-10 GPM 20-28 kW

How many gallons of hot water does a shower use?

The average American shower uses 17.2 gallons (65.1 liters) and lasts for 8.2 minutes at average flow rate of 2.1 gallons per minute (gpm) (7.9 lpm).

How many gpm of hot water does a shower use?

Worksheet for Estimating Peak Hour Demand/First Hour Rating *

Use Average gallons of hot water per usage
Shower 20 =
Shaving (.05 gallon per minute) 2 =
Hand dishwashing or food prep (2 gallons per minute) 3 =
Automatic dishwasher 7 =

Why is tankless water heater installation so expensive?

Tankless water heaters have a higher initial price compared to tank heaters, costing homeowners between $1,200–$3,500. The higher cost is a result of a more labor-intensive set-up, as new gas and water lines are required for installation. For electrical tankless heaters, new electric wiring will need to be installed.

Which is better hot water tank or tankless?



According to Energy.gov, “For homes that use 41 gallons or less of hot water daily, demand (or tankless) water heaters can be 24% to 34% more energy efficient than conventional storage tank water heaters.” Tankless water heaters (if gas-fired) will save homeowners over $100 annually the longer they remain in service.

How long do tankless water heaters last?

20 years

Most tankless water heaters have a life expectancy of more than 20 years. They also have easily replaceable parts that may extend their life by many more years. In contrast, storage water heaters last 10–15 years. Tankless water heaters avoid the standby heat losses associated with storage water heaters.

How much should it cost to install a tankless water heater?

Tankless water heater installation costs $800 to $3,500 on average. Tankless hot water heater prices are $300 to $2,100 for a gas or electric on-demand system, plus $300 to $2,500 for installation labor. Tankless water heaters save $40 to $200 yearly by reducing energy costs by 8% to 34%.

How long does it take for water to get hot with tankless water heater?



Instant Hot Water

Tankless units take about 15 seconds to bring water up to temperature, but you still have to wait for that hot water to arrive at your shower head or faucet, just as you do with a tank-type heater.

How long does it take to install a tankless water heater?

between one to three hours

Additional time is required to install new power and water lines and air vents. Afterward, the tankless unit must also be mounted and connected. Tankless to Tankless Installation: This generally takes between one to three hours.