If you need to replace your home’s old water heater, there are two core options: tank and tankless. Tank water heaters are the traditional choice. Tankless or instantaneous water heaters are a more modern home improvement option. Let’s explore the pros and cons of both types.
Electric, Gas, or Oil
With both tank and tankless systems, you have the choice of either electric or fuel-burning. Electric water heaters tend to be less expensive initially but cost more over the life of the equipment. Natural gas is the most popular fuel for water heaters, but your home needs access to a gas line. If you lack it, you can store either propane or fuel oil in a tank.
Even Fuel-Burning Water Heaters May Require Electricity
All fuel-burning tankless water heaters require electricity, too. They use it for ignition and, potentially, displays and control boards. Fuel-burning tank waters don’t use electricity for ignition, but they may require it for displays, smart features, and more.
Condensing vs. Non-Condensing
If you opt for a fuel-burning tank or tankless water, you have the option of a condensing system. These units have an additional heat exchanger and cost more because of it. They save money over time because they improve efficiency by extracting heat from exhaust gases.
Efficiency
Tank water heaters are inherently less efficient. They store hot water and have to expend energy keeping it at the desired temperature. Tankless systems heat water on demand. You’ll see this difference reflected in the Uniform Energy Factor (UEF). UEF is what the U.S. Department of Energy (DOE) uses to measure water heater efficiency. The higher the UEF, the more efficient the system.
Household Water Consumption
How much more efficient a tankless water heater will be depends on consumption. The typical American household uses 41 gallons of hot water a day. At that level of consumption, a tankless system uses 24-34% less energy than a traditional water heater. At twice that amount, the energy savings fall to about 8-14%.
Electric vs. Gas
Electric water heaters are technically more efficient in general, but fuel is usually preferable due to the cost of electricity. There is an exception. In small homes with only one or two occupants, electric tankless water heaters can be more efficient than their fuel-burning counterparts.
Rebates and Tax Credits
The Environmental Protection Agency (EPA) sets energy efficiency standards for water heaters and other appliances. If a water heater meets its standards through independent testing in a lab, the EPA awards it ENERGY STAR certification. Water heaters with the ENERGY STAR label may make you eligible for rebates and tax credits.
Short and Long-Term Costs
Equipment and installation costs are less for tank water heaters. They’re higher for tankless water heaters. There may also be additional one-time costs if you need plumbing and/or electrical upgrades to accommodate a tankless system. Tankless systems offer lower operating costs and have a longer lifespan. The typical tank water heater lasts 10 years. The typical tankless water heater lasts 20 years. Efficiency and longevity are why tankless systems are often better values despite costing more initially.
Installation Footprint
Tank water heaters take up a lot more space. Many homes even have dedicated water heater closets because of it. There are short and tall form factors available that can help you save space. Tankless systems are much smaller. You can install them on practically any wall, including outdoors. You can even install them out of sight, such as in an attic.
Sizing
Sizing your water heater correctly is integral to both tank and tankless water heaters. That said, the approach to sizing them is different.
Tank: Gallons
Our plumber will size your tank water heater based on the number of gallons the tank can hold. The goal is to have enough gallons to meet your daily demand. If you have less than that, you’ll run out of hot water and not have any until the system heats more.
A 50-gallon tank is typical for the average household of four people. There are tanks ranging from 10 to 40 gallons for small households. Tanks as large as 120 gallons are readily available for larger homes. The resident count isn’t the only consideration. You may have to move up a capacity level or two if you have a dishwasher or a high number of bathrooms.
Tankless: Gallons per Minute
Plumbers size tankless water heaters in flow rate or gallons per minute (GPM). Manufacturers rate their tankless water heaters for GPM at a particular temperature rise. Rise is the difference between the temperature of your water supply and the target temperature of your hot water. You need enough GPM to feed all the fixtures and appliances you want to run at the same time. If demand exceeds GPM, you won’t run out, but you will experience low water pressure.
Sizing for Added Demand
Your hot water needs may vary throughout the year. Perhaps you have adult children home from college during breaks and you like to host large family gatherings during the holidays. Sizing a tank water heater for that additional demand isn’t practical. You’ll be paying for the added capacity every day even though you wouldn’t be using it most days. That isn’t an issue with tankless systems, and it’s one of their great advantages. Opting for a higher GPM will cost you more up front. Yet, it’ll only cost you more in operating costs when you actually use the additional capacity.
Maintenance Requirements
Most water heater warranties require annual maintenance. For all types of water heaters, maintenance includes testing valves and checking insulation on exposed pipes. Our plumber will also check any filters and either clean or replace them as needed. Tank systems require flushing to remove sediment and limescale from the tank. We must also check the sacrificial anode rod and replace it as needed. Typically, they last about three years. For tankless systems, we must descale them to avoid limescale buildup on the components. Our R.P.S. Home Protection Plan is a good way to save money on maintenance and not have to worry about remembering to schedule it every year.
Water Hardness
Hard water is a concern for all water heaters. It shortens water heater lifespan, decreases energy efficiency, and increases operating costs. This is why regular flushing or descaling is so important. Hard water is particularly damaging to tankless systems. If you have hard water, it’s generally recommended that you add an anti-scale device to it. If you want a home-wide solution, we can install a water softening system instead.
Hot Water Delay
Tank water heaters provide hot water faster because they preheat the water. The delay will be longer with a tankless system, and the added delay can be even longer in a large home. Choosing a system with a recirculating pump or adding a pump is one way to overcome this issue.
Would You Like to Install a New Water Heater in San Jose?
Ribbs Plumbing Services installs both tank and tankless water heaters in San Jose, CA and throughout the surrounding areas. Our plumbers are available for camera inspections, drain cleaning, and sewer and septic services, including trenchless repairs. We pipe and repipe gas, water, and sewer lines. Our team also hooks up appliances and installs and repairs bathroom and kitchen fixtures, water filtration systems, garbage disposals, and sump pumps.
Call today or contact us online to schedule a service appointment or in-home consultation.
