There are practical matters to consider when replacing your current water heater so here’s a list of questions you need to answer before you start the selection process.
For instance, is your current water heater located in your garage so it’s easy to access or in a small space where there’s no extra room?
Questions for water heater selection
- Is your current water heater natural gas, propane gas or electric?
- Is the water heater for a mobile home?
- Where is your water heater located?
- Is it easily accessible?
- What’s the height available for installation? (measure from floor to closest permanent obstruction above)
- What is the diameter of the current water heater? (measure across the top of the unit)
Cost of yearly operation
If you’re wondering what a new water heater will cost you to run, most have an “Annual cost of operation” listed in their specs. You should remember the amount listed is an estimate. The exact cost will depend on how much hot water your family uses in a year. More showers or loads of laundry means more hot water and that translates in more money.
How much hot water do you need?
This is probably the most important question you need to ask yourself as you don’t want to invest in a new water heater only to have the same problem as before-having to take a cold shower! Before we discuss HOW much hot water you need, let’s go over the factors affecting hot water output.
- Gallon size
- Recovery (90-degree rise)
- First hour output
This is simply how much hot water the tank stores at 1 time. This is important because you want a tank big enough so that’s there’s plenty of hot water during the first hour of use, which is usually in the morning.
Input is the amount of gas or electricity used per hour to heat water in the tank. Input is talked about in BTUs (British Thermal Units) for gas water heaters and watts for electric water heaters. The higher the input number, the faster the water heater can work to heat water.
Recovery is crucial as when hot water is used, it needs to be replaced quickly so that you don’t run out of hot water. The recovery rate converts the BTUs or watt input into gallons heated in 1 hour (or GPH) so a 40,000 BTU can heat 41 gallons in 1 hour.
FYI-The 90-degree rise refers to the fact that the water temperature is raised by 90 degrees Fahrenheit.
First hour input
Sometimes called First Hour Rating, it tells how much hot water will be provided during the 1st hour you start using hot water. It’s figured by combining the tank’s storage capacity with the recovery rate during the first hour of use.
It’s not hard to figure out how much water you need, just compare the number of people in your family with the First Hour Rating. Remember to take into consideration the number of bathrooms in your home.
How much water do you use?
For example, a family with 3-4 people that live in a house with 2 or 2.5 bathrooms should get a water heater with a minimum First Hour Rating of 67 gallons. The recommended tank capacity of an electric water heater is 50 gallons whereas a gas water heater is 40 gallons.
A couple of things to note-If you have an over-sized tub or whirlpool that you use frequently, add 10 gallons. You should also add 10 gallons for every teenager in your home. Please remember these are minimum requirements.
What is EF?
EF stands for Energy Factor and it measures a water heater’s energy efficiency. It’s based on recovery efficiency or how efficiently heat passes from the energy source (gas or electric) to the water and preventing heat loss during operation.
The higher the EF, the more energy efficient it is. Electric water heaters usually have higher EF ratings than gas ones.