If your home needs a new water heater, it’s a great time to reevaluate your household’s needs. Sizing a water heater properly isn’t necessarily complicated. However, it can vary based on the type of water heater you’ll be installing. We help Melbourne, FL residents pick the right water heaters on a daily basis using some simple information about their household usage here at Benjamin Franklin Plumbing. Here’s how to decide the size of the water heater you need for your home.
Sizing a Standard Tank Water Heater
Sizing a tank-style water heater for your home is straightforward. Simply estimate the capacity you need in gallons based on household size. Most households need water heaters that are around 40 gallons. Here’s how to choose the right one based on the number of people in your household:
- One to two people: 25 to 40 gallons
- Two to four people: 36 to 50 gallons
- Three to five people: 45 to 60 gallons
- Five or more people: 60 gallons or more
When sizing water heaters for large households, the trick is to add 10 gallons for each extra person. Household size should get you in the ballpark range of where you need to be with water heater size. However, usage also matters.
Tank-style water heaters all come with something called a first-hour rating. This rating represents the number of gallons of hot water the water heater is capable of supplying per hour when starting with a full tank of heated water. A water heater unit’s first-hour rating can vary based on whether it uses a burner or element. The size and capacity of the burner or element will also determine the first-hour rating.
What this rating really tells you is what your water heater is capable of handling during a one-hour period of heavy usage in your home. Think of that moment first thing in the morning when everyone is running in and out of the bathroom to shower and brush their teeth while you’re also trying to get ahead of the laundry pile by popping in an early load. Of course, first-hour ratings also represent what a water heater is capable of during any peak time of water usage in your house. This period could also be the hour when everyone gets home from work or school to begin cooking, handling loads of laundry, showering, and running a load of dishes before bed.
When shopping for your new water heater, look for models that have first-hour ratings that align with your peak-usage needs. Keep your average water usage of gallons per minute per person during peak time in mind when factoring in how many people are in your household. Remember that everything from a quick shave to washing hands with warm water during food preparation will add gallons to each person’s usage.
Sizing a Tankless Water Heater
Also known as a demand-type water heater, a tankless water heater doesn’t store hot water for usage the way that a tank-style water heater does. Tankless water heaters heat water through the unit on demand each time you turn on a faucet. When a faucet is activated, cold water flows into the tankless heater to be heated by a gas burner or electrical element. The benefit of tankless water heaters is that you won’t need to wait for water to heat up if you use up your supply. Tankless water heaters provide a constant flow of hot water.
As a result of this fundamental difference, tankless water heaters aren’t rated by size. You must instead look at the maximum temperature a tankless water heater is capable of achieving at a specific flow rate. You have to know your household usage pretty well to be able to size a new tankless water heater. A plumber will be able to help you estimate water usage if this is all new to you. However, the basic formula involves taking stock of the number of fixtures or appliances that pull hot water that you can expect to use at any given time in your home.
Flow rate is measured in gallons per minute (GPM). Once you’ve taken stock of the water-using fixtures and appliances in your home, add up their flow rates in gallons per minute. If your household routinely runs several faucets or water-using appliances at once, you’ll need a greater flow rate to keep up with demand. The average household has a flow rate between 6 GPM and 12 GPM. This works out to between 100 and 120 gallons of water used daily.
Making Sense of Water Heater Sizes
Ultimately, choosing the right water heater size comes down to balancing daily water usage with the size of your household. It’s generally wiser to go bigger in order to give your household a buffer. Trying to save a little bit of money instead of jumping up to the next size when you’re on the cusp can leave your household with cold showers or dishes that don’t come out clean. The pros at Benjamin Franklin Plumbing are here to help you pick an appropriate size for your new water heater. We offer access to all the best tank-style and tankless water heaters on the market today. Our team will help you find the most efficient model based on your household’s daily water needs. We also provide expert installation. Make sure hot water is always waiting in the tap when you need it! Contact Benjamin Franklin Plumbing to work with Melbourne’s top plumbing company!