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Comparing a 3.2 gpm tankless water heater to a forty gallon tank type heater is possible. For example, if a **tankless unit produces hot water** at 3.2 gallons per minute, this rate of flow will run a 40 gallon tank type heater out of water in only ten minutes.

## How Many Gpm Should a Well Pump Produce?

5 gpm (two fixtures running simultaneously at 2.5 gpm) is a good estimate of peak demand, for the typical household. Water wells that **reliably yield 5 gpm** should be able to meet peak and daily needs for most residences. Wells yielding less than 5 gpm, however, are sometimes the only water source available.

## How Many Gpm Do I Need for a Family of 4?

A family of 4 should look for a tankless water heater that can produce 7 gallons of hot water per minute. Most families use about 6.5 gpm during peak times. To determine the **tankless water heater size**, you’ll need to know how many appliances your family will use simultaneously.

What size tankless water heater do i need for a family of 5? In short, a family of 5 would need a 10 gpm gas tankless heater or 27 kw electric tankless heater if you live in the northern part of the usa, where the input water has a lower temperature. The tankless heater has to work extra hard to bring the water temperature up to 110˚f or 120˚f.

How many gpm should a 3 bathroom house have? Compare that with **standard flow rates across** the u.s. For the standard home, a typical gpm looks something like this: kitchen faucet: 2-3 gpm. Shower: 1.5-3 gpm. Dishwasher: 2-4 gpm.

## How Many Btus Do I Need for My Tankless Hot Water Heater?

**between 150,000 and 200,000 BTUs**

Dishwasher | 0.5 – 1.0 GPM |
---|---|

Shower | 1.5 – 2.5 GPM |

Bath tub | 2.5 – .0 GPM |

Jacuzzi/Hot tub | 4.0 – 5.0 GPM |

How many btu does a gas tankless water heater use? **In order to get the water to a sufficient temperature, the units use a high volume of gas**, typically between 150,000 and 200,000 btus, which in most homes requires the upsizing of a gas line.

**How to Select the Right Size Tankless Water Heater**

- Determine the maximum number of devices you want to run and their total flow rate. Then, add up their flow rates (gallons per minute).
- Determine required temperature rise.
- Sizing Example: An average shower will be between 104–106° and uses 2.6 gallons of water.

Sizing Guide for Residential Tankless Water heater | ||
---|---|---|

1-2 people | High | 40-50 |

2-3 people | Regular/Low | 40 |

High | 40-50 |

## What Size Tankless Water Heater Do I Need for a Family of 3?

**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 2? | 6-8 GPM | 10-18 kW |

What size tankless water heater do I need for a family of 3? | 7-9 GPM | 15-23 kW |

Is a 40 gallon water heater enough for 3 people? Typically, the rule-of-thumb is that you want a 40 gallon tank for 1 to 4 people, a 50 gallon tank for 4 to 6 people, and a 50 gallon high recovery or 75 gallon tank for 6 to 8 people. **Energy consumption for 40 and 50 gallon standard water heaters is quite comparable**.

Is a 30-gallon water heater enough for 3 people? 1-2 people need a 30-gallon water heater. 2-3 people need a 40-gallon water heater. 3-4 people need a 40-50 gallon water heater. 5 or more people need a 50-**80 gallon water heater**.

## 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.

**In general, we use 50 to 100 gallons per person per day in our homes (200 to 400 gallons per day for a family of four). Estimating Home Water Use Needs.**

Appliance | Water Use |
---|---|

Bathroom sink | 2 gallons per minute of use |

Shower or tub | 5 gallons per minute of use |

Is 1.75 gpm enough for a shower? Since 1992, a maximum of 2.5 gpm is the federally mandated flow rate for new shower heads. This means no more than 2.5 gallons of water should flow out each minute. The **gpm flow rate** for shower heads has decreased over time.

## What Size Tankless Do I Need to Replace 50 Gallons?

To replace a 50-gallon water heater, you would, roughly speaking, need: 10 gpm gas tankless heater or at least a 27 kw electric tankless water heater if you live in the northern part of the usa. 7 gpm gas tankless heater or at least an 18 kw electric tankless water heater if you live in the southern part of the usa.

What size of tankless hot water do i need? Average temp. For example, if you are running 2 showers at the same time, you will need 5 gallons of **hot water per minute** from the tankless water heater. If you were running a shower and the washing machine at the same time, you would need 4.5 gallons per minute from the water heater.

Can i replace my tank 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.

How many showers can you get from a 50 gallon water heater? On a national average of 8 minutes to take a shower you can can get 2 showers out of a 50 gallon water heater. Based on 17 minutes of **hot water run time** at 2.1 gallons per minute shower head flow calculation also from a 50 gallon water heater.

## Can You Oversize a Tankless Water Heater?

**If you install a unit that’s too small, you won’t have enough hot water to meet demand**.

Can tankless water heater be too big? **If the tankless water heater you select is too small, you won’t get enough hot water if multiple fixtures are running**. If it’s too big, you’ll end up paying a lot more for something you can’t get the full use out of, though this can be okay if you plan to add on to your home later.

**Should i oversize tankless water heater?** As suggested when selecting a tank-type heater, you don’t want to buy an oversized or undersized tankless water heater, as it will result in unnecessary issues such as the rising upfront price, operating costs, and wasted water, and energy – affecting your budget and time.

Does size of **tankless water heater matter**? By bob d. Size matters when it comes to your tankless water heater. In fact, it is the most important part of choosing a new unit for your home. Having a water heater that is too small will result in it not being able to produce enough hot water for your household demand.

What happens if your water heater is too big? When your tank water heater is too big for your home, you have ample hot water, but issues occur in other areas. **An oversized water heater heats more hot water than your household needs**, which wastes energy.

## How Many Gpm Do I Need?

A toilet will **normally use** about 2.2 to 5.0 gpm, a shower from 2.5 to 5.0 gpm, a bathtub from 4.0 to 8.0 gpm, a bathroom or kitchen faucet from 2.5 to 3.0 gpm, a dishwasher from 2.0 to 3.0 gpm, and a washing machine from 4.0 to 5.0 gpm.

How many gpm hot water heater do i need? Flow rates we suggest using 2.5 gpm for a shower and 1.0 gpm for a bathroom as a reference point in determining your **total simultaneous water needs**.

How many gpm is 2 showers? That means an estimated 1.2 trillion gallons of water are used for showering annually in the united states. Standard shower heads use 2.5 gpm, but to earn the watersense label, a product must use no more than 2 gpm and still meet strict performance requirements.

## How Many Btus Does It Take to Heat 40 Gallons of Water?

Calculate the btu. If you have a 40-**gallon water heater**, that is 40 multiplied by 8.33, or 333.2 pounds of water. So you need 333.2 btu to raise the water 1 degree fahrenheit.

**How many btu does it take to heat a gallon of water? 8**.

How long does it take to heat 40 gallon tank? A gas water heater will recover in half the time of an electric unit. A 40-**gallon gas water heater** can recover in about an hour. Recovery for a 40-gallon electric water heater takes about two hours.

How long does it take a 50-gallon water tank to heat up? Water coming into a 50-gallon tank at 40 degrees takes just 53 1/2 minutes to reach 120 degrees. For 60-degree water entering the tank, calculate about **40 minutes needed** for the water to reach the 120-degree temperature. For 70-degree water, it would take 33 minutes.

Is **36000 btu good** for a water heater? At home depot, a 40,000 btu/hr. Input, 50-gallon water heater is considered quick recovery. They consider 36,000 btu/hr. To be standard recovery. Try to buy a 50,000 btu/hr. Or higher 50-gallon water heater from home depot.