The Energy Efficient Water Heater
Water heaters are an essential household appliance that provide us with hot running water for showering, washing dishes and laundry. They come in different forms such as electric, gas, fuel oil or solar.
A traditional storage tank water heater is powered by a thermostat that records the temperature of the water inside and when readings drop below prescribed temperatures, kicks into action heating water back up to optimum levels.
Size
A water heater is often one of a home’s most underappreciated appliances. Hidden away in a basement or dark utility closet, it works reliably for decades with little maintenance. However, the size of your water heater can have a significant impact on your energy bill.
Most households in the United States use storage tank water heaters, which can hold between 40 and 100 gallons of hot water. Choosing the right size depends on how many people live in your household and what are your peak water usage times (such as morning or evening). An undersized water heater is constantly working to meet demand, which can increase your utility costs.
The temperature setting of your water heater also impacts energy consumption, especially for conventional tank-type electric water heaters. Set your hot water temperature between 120 and 140 degrees Fahrenheit, the optimal range for your needs.
A hybrid tank-type water heater that uses a combination of natural gas and solar heating can save you money on your energy bills. These units are up to 3 times more efficient than traditional water heaters. However, it is important to understand their limitations. A gas tankless hybrid water heater can only provide a limited amount of hot water per hour, even when it is operating at full capacity. This is known as the first-hour rating and you can find this information on the EnergyGuide label or in manufacturer’s literature.
Efficiency
The energy used to heat water accounts for a large portion of the average household’s energy bill, so electric boiler it pays to maximize efficiency. But there are three places where a water heater can lose energy: during the conversion from electricity to hot water, while the water is sitting in the tank (if you have a traditional storage-tank model), and when the hot water is piped to different parts of your home.
Cold water enters your home’s water line through a shut-off valve, then travels down the dip tube until it reaches the bottom of the tank where it’s heated by a heating mechanism. This process is accelerated by the presence of hard minerals, which form sediment on the tank’s interior surface. The sediment reduces the heating efficiency of your tank and can tamper with the thermostat, causing the temperature to rise higher than it should.
Keeping the water heater’s drain valve open can help flush out sediment to prevent this problem. The water heater also has a shut-off valve that blocks water from flowing back into the unit, and a pressure-relief valve that opens to relieve excess pressure inside the tank. You should test these components regularly to ensure they work properly. If your water heater is more than 8 years old, a replacement might be in order. A rusted or leaky tank could lead to discolored water and expensive repairs.
Installation
A water heater is a heavy metal tank with a built-in dip tube that holds 40 to 60 gallons of hot water under 50 to 100 pounds per square inch (PSI). The inner tank has a steel liner and is covered by a protective jacket of polyurethane foam or similar material. The jacket is also insulated. A gas or electric water heater has a vent pipe to allow air in to the flame and exhaust gases out through the flue. Building codes may require a direct venting system instead of a chimney for safety and energy efficiency.
During installation, the tank is connected to your home’s plumbing with copper tubing or flexible plastic piping known as PEX. If you choose PEX, review manufacturers’ literature to familiarize yourself with the specifics of this system before starting work. Remember that working on an energized circuit can result in severe injury or death. Work safely by using a volt meter and circuit tester to make sure all wiring is properly de-energized before you begin work.
Before connecting your new water heater, shut off the cold and hot water valves situated atop the electric tankless heater tank. Turn off the power to your gas or electrical water heater, then use a garden hose connected to the drain valve on your tank and put a bucket underneath to drain five to ten gallons of hot water from the tank, dumping it in a nearby drain. Remove the anode rod securing the sacrificial anode at the top of the tank, and inspect the anode rod for signs of corrosion. If it’s corroded, replace it.
Maintenance
As a major appliance, the water heater needs regular inspections by a professional plumber to ensure it is working as it should. In addition, routine maintenance reduces the risk of future problems and expensive repairs.
Check the temperature pressure relief valve on a regular basis, usually every two to three months. This is designed to release excess pressure within the tank and prevent water and steam from escaping. To test the valve, remove the drain pipe attached to the valve, place a bucket underneath, and then lift the valve lever. If water and air escapes the valve, it is operating correctly.
Perform a bacteria flush on your water heater at least once per year to eliminate bad odors and remove sediment e.g. scale, rust, and bits of corroded anode that collect at the bottom of the tank.
Make sure you know how to turn off the power and gas to the unit by turning off the breaker (electric units) or shutting off the gas supply line (gas units). Always keep flammable or combustible materials away from the unit, especially during maintenance and when examining it for leaks. The water inside a hot water heater is very hot, so be careful and allow it to cool before touching. If you are using a gas unit, follow the instructions on the unit’s manual for relighting the pilot light.