What Size Tankless Water Heater For Family Of 5?

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On-demand, limitless hot water is available via tankless water heaters.

They eliminate standby energy losses, which can save your electricity costs by almost 30%.

But if you have a family of 5 members, the first question you would be asking is what size tankless water heater is for a family of 5.

Here we are, to help you out in finding the perfect-sized water heater for your family.

What Size Tankless Water Heater For a Family Of 5?

If you have a family of five and you need a hot water tank, you’ll need one that’s at least 50 gallons in size.

Based on other factors, like usage and power system, you may even need an 80+ gallons heater.

Available Sizes Of Tankless Water Heater For Family Of 5:

Family members	Usage	Capacity
5 Members	Electric	Gas
Regular/Low	80	50
High	80+	75

Determine The Size Of A Tankless Water Heater For A Family Of 5:

Just picking a size based on some statistics is not a good idea.

You shall consider all the relevant factors that have an impact on the size of the tankless water heater.

So, consider the following things wisely before you opt to buy one.

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How Big Is Your House?

There is a range of sizes available for tankless water heaters.

Virtually all contemporary water heaters have the capacity to steam your whole home’s water supply in its entirety. 

If you choose a model with a lesser capacity, you could find that you can only heat the water that is used in some of the bathrooms in your home.

This would be an inefficient use of the water heater.

Traditional storage tank heaters, can only hold and heat the amount of water that you anticipate using at any one time.

But tankless heaters, when properly designed, are capable of heating an unlimited quantity of water.

Don’t pick a unit so small that it can’t supply enough hot water to run all of your showers and sinks at once.

The Number Of Family Members:

Consider household size and peak consumption when choosing a tankless water heater.

Calculate peak hot water demand based on the number of users. Choose tank size accordingly to ensure sufficient hot water supply.

The water flow rate inside your house:

Because the water steams as it enters your home, tankless water heaters are clearly different from conventional tank heaters. 

This implies that the flow rate generated by your heater controls how much water is released from your faucets.

If you take this into account, you may use many faucets or shower heads simultaneously without reducing water pressure.

A simple calculation:

If a shower head typically emits 1.8 gallons of water per minute, a second shower may begin to emit 1.8 gallons of water per minute alongside the original one.

To be practical, both the showers and the tankless water heaters should be able to generate sufficient flow.

The combined flow rates of the two showers may be used to determine the optimal flow rate for the tankless water heater.

First shower uses 1.8 GPM + the second shower uses 1.8 GPM = for a total of 3.6 GPM flow rate.

While those two showers are operating, the kitchen or another bathroom may have another one running. So, it further increases the combined need for flow rate.

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Typical GPM Rates:

Below, we’ve provided some average flow rates to assist you to estimate the water output of your faucets.

Depending on the layout of your home and the efficiency of your appliances, the actual flow rates may vary. 

• 0.5 and 1.0 gallons per minute = bathroom sink faucet

• and 2.0 gallons per minute = showerhead

• 2.0 and 6.0 gallons per minute = typical range for a kitchen faucet

• 1.5 to 2.5 gallons per minute = dishwashers

• 2.5 to 3.5 gallons per minute = top-loading washing machine

3. Rate of temperature increase:

After figuring out how much water flows through each fixture, you are a step ahead.

You can calculate the amount of heat your heater has to produce to meet the desired temperature at the fixtures.

To calculate the necessary temperature increase, you have to consider two things.

The incoming water temperature and the desired temperature for the water coming out of your faucet.

A simple calculation:

If the water flowing into your house is 45 degrees Fahrenheit and the water temperature in your shower is 105 degrees Fahrenheit, then you need a 60-degree temperature boost.

From the equation: Shower temperature prediction (105°F) (-) incoming water temperature prediction (45°F) = The minimum Heat-Up for your heater is 60°F.

Your water heater must continuously heat 60 degrees Fahrenheit (C) worth of water.

Important consideration:

It’s also important to keep in mind that some US states are often warmer or colder than others, which might produce a difference in average ground temperatures throughout the country.

Estimates put the peak temperature in certain states at 75 degrees. For other states, this is at about 35 degrees.

The groundwater temperature in your state is an important factor in determining the efficiency of your heater.

If you’re unsure of what it is, you can make the assumption that it is 40 degrees. It will make sure you don’t underestimate the required temperature rise.

FAQs About Tankless Water Heater For A Family Of 5

Final Words:

You know what size a tankless water heater is for a family of 5.

Yet, to summarize it in a sentence make sure you account for peak consumption periods after calculating the water flow rate and needed temperature rise for regular hot water usage. 

Don’t hesitate to let us know if there’s anything else you’re curious about despite our responses.