Proper sizing is important prior to select and installing a tankless, but in general the average rules for sizing the correct water heater for a household are roughly: 3.5 GPM for 1-2 fixtures simultaneously. 5 GPM for 2-3 fixtures simultaneously. 7 GPM for 3-4 fixtures simultaneously.
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.
An average 3-bedroom home, less than 2500 square feet, will probably require a 1000-gallon tank.
You can go with a small tank and a small tankless water heater at the same time. You install this as a single device (1.5 gal per minute) tankless water heater with the output going to the tank and the tank feeding your household. If you need a lot of hot water quickly both water heaters run at the same time.
Before you commit to buying a tankless water heater, the primary drawbacks to know include: Higher upfront costs. Tankless water heaters are, on average, quite a bit more expensive to buy and install than tank water heaters. Access to fuel.
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.
Here are some basic recommendations for water well flow rate based on the number of bedrooms and bathrooms in your home: Two bedrooms: 1 bath = 6 GPM; 1.5 bath = 8 GPM; 2 bath = 10 GPM. Three bedrooms: 1 bath = 8 GPM; 1.5 bath = 10 GPM; 2 bath = 12 GPM.
Sizing Tankless or Demand-Type Water Heaters
List the number of hot water devices you expect to use at any one time. Add up their flow rates (gallons per minute). This is the desired flow rate you'll want for the demand water heater.
With a standard showerhead, around half a gallon more water will emerge each minute, so a 10-minute shower would use somewhere close to 25 gallons. *1 gallon = 4.54 litres.
The average water bill in the U.S. is $49 per month, with most bills falling between $40 and $60 per month. However, monthly water bills range from $15 to $100+, depending on the household size, water usage, and location. A typical family of 4 uses over 300 gallons of water per day.
In general, a 40- to 50-gallon tank is sufficient for an average household of 2 to 3 people, increasing by 10 gallons per additional person in the home. In a tankless water heater, the capacity is measured by flow rate, calculated in gallons per minute.
The right tankless water heater can definitely take care of all your family's hot water needs, including taking multiple showers at once. If you're considering upgrading to a tankless water heater, it's essential to work with experienced professionals.
Small households of two people need a tankless heater with a flow rate of 6 to 8 GPM, while a larger household of four people requires a flow rate of about 8 to 10 GPM. Remember to factor in temperature rise when deciding how big of a tankless water heater you need for your household.
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.
Making sure you have a properly sized water heater is very important. If your water heater is too small, your home won't have enough hot water to meet demand, which is an obvious inconvenience, and overloading the unit may cause premature wear and tear. There's no benefit to oversizing a tankless water heater.
The typical range for tankless heater installation is between $5,400 and $7,400 averaging out to around $6,400 (including the water heater, warranty and tune ups). The tankless installation without the unit can cost between $1800 and $3500, averaging out to around $2650. One of the big variables is labor rates.
If your home has two bathrooms and 2 or 3 residents, consider a water heater of 190,000 BTUs. If your home has three bathrooms and 3 to 5 residents, consider a water heater of 380,000 BTUs.
Selecting a Whole House Water Filter
Typical showerheads flow 2.5 to 5 GPM, toilet 5 GPM, dishwasher 3 GPM. Depending on the size of your house and family your water flow rate requirements may range from 15 - 40 GPM.
In general, a tankless water heater with a GPM of 7-9 is ideal for a family of four, but it's crucial to consider other factors such as temperature rise.
Homeowners can receive a tax credit of 30% of the project cost, up to $2,000, for Heat Pump Water Heaters installed between January 1, 2023, and December 31, 2032. Gas Storage Water Heaters, Tankless Gas Water Heaters, and Boilers also qualify for a tax credit of 30% of the project cost, up to $600.
Advantages and Disadvantages of Tankless Water Heaters
The initial cost of a tankless water heater is greater than that of a conventional storage water heater, but tankless water heaters will typically last longer and have lower operating and energy costs, which could offset their higher purchase price.
Tax Credits for Water Heaters
Rebates are available for high efficiency gas fired tankless, gas-fired storage and for heat pump water heaters. Gas-fired tankless with UEF ≥ . 95 are eligible for up to $600 in rebates.