An average residential water heater lasts about ten years. As a heater nears the end of its lifespan, a variety of problems can crop up that will impact both its efficiency and effectiveness. In practice, this means that your older water heater may be costing you more money than necessary on utility bills while failing to heat your water to a reasonable temperature. When the time comes for replacement, this can make it especially challenging to decide on a new model. Should you buy a similarly sized tank? Was your old heater insufficient for your needs or only too old to keep up with demand? This article will help you to answer these questions so that you can make an informed choice on your replacement heater.
Understanding Tank Size
For a traditional water heater, tank size is the primary determining factor when it comes to meeting household demand. If your tank is too small, your heater will be unable to keep up with the demand from multiple fixtures and appliances. If your tank is too large, you will waste money on both installation and operating costs. Like Goldilocks and The Three Bears, choosing a water heater that is "just right" is essential for cost and efficiency. It can be tempting to look at the size of your water heater and decide to go with a similar model, but there are more exact (and surprisingly simple) ways to choose a replacement.
The Problem of Peak Demand
Traditional water heaters store hot water in a tank so that it is ready as needed. Although both the hot water outlet and cold water inlet pipes on a water heater may be located at the top of the tank, the cold water pipe delivers water to the bottom of the tank. As you use hot water throughout your home, more cold water flows into the tank. The water heater then heats this cold water, allowing it to rise to the top of the tank for further use. When demand for hot water is high, the tank may be unable to warm cold water quickly enough to keep up. You can calculate your demand easily using this chart.
Determining if your tank is large enough is a matter of comparing your household's peak demand for hot water with the size of a tank and its first-hour heating rating. As the name implies, the first-hour rating is the amount of hot water the tank can produce in an hour. In other words, this is how much water you will get before your hot water "runs out." Using the chart above, compare your current water heater's first-hour rating to your calculated hot water demand. If the two values match, then you can replace your old heater with a similar model. If not, you may need to consider sizing up your replacement.
Getting It Right The First Time
It may seem a bit arduous to calculate your total hot water usage for a simple water heater replacement, but these are not cheap appliances. More importantly, getting a water heater sufficient for your household will help to keep your utility costs in check going forward. If you are uncomfortable calculating this number yourself, any plumber can help you to audit your home's hot water needs to ensure that your new water heater is perfectly sized for your family.
For more information, reach out to a company like Silverdale Plumbing & Heating Inc today.