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Water Heater Basics

Denver Water Heaters provide hot water for your whole house. It’s essential to pick a model that fits your home correctly and can meet your family’s needs.

Water Heater

It’s also important to look at energy efficiency and cost. Energy costs can add up quickly, so estimate your annual operating costs.

Traditional storage tank water heaters are the most common and affordable option for homeowners. They come in sizes ranging from 20 to 80 gallons and can be fueled by either electricity or natural gas. These tanks use a simple yet clever process based on the law of convection to heat your home’s water. Cold water enters the tank through a dip tube and is heated by a heating element or gas burner that sits inside the bottom of the tank. As the water heats, it rises and exits through a hot water discharge pipe located at the top of the tank.

This pipe is responsible for supplying hot water to all of your home’s sinks, tubs and appliances that require it. This pipe may also have a shutoff valve, which is usually identified by a red handle. The dip tube and hot water discharge pipe are surrounded by a layer of insulation that serves to reduce energy loss from the tank. Insulation can be supplemented by adding a fiberglass insulation tank jacket, which is relatively inexpensive and easy to install.

While the majority of a tank-type water heater is made of steel, there may be a glass liner covering parts of the inside of the unit. Most models will have a metal flue pipe running through the center of the unit that’s fitted with a spiral-shaped metal baffle. This is designed to capture and transmit heat from the exhaust gases to the surrounding water, maximizing the efficiency of the unit.

The most expensive part of a conventional tank-type water heater is its fuel source, which can be electric or gas. When the thermostat on your water heater senses that hot water is being used, it turns on the heating element or gas burner to start heating the water. As the water heats, it will rise to the hot water discharge pipe at the top of your tank and exit the unit when you open a faucet or appliance. The water will then flow through your home’s plumbing systems and be consumed. This process is repeated as needed, ensuring that you never run out of hot water.

Tank-less

With a tankless water heater, your supply of hot water is virtually limitless. Also known as on-demand units, they use electricity or natural gas to heat water only when it is needed. This saves energy compared with conventional models and can reduce utility bills. A tankless water heater may require more up-front installation costs, but the payback comes from energy savings and rebates available through local and state programs.

Tankless units are more compact than traditional tank models and are wall-mounted to free up floor space in your home. This makes them a good choice for smaller homes, especially those with tight spaces. They are also more resilient than tanks, which can leak and cause damage to your home or cause Legionella bacteria to grow in them.

You can install a whole-house tankless water heater or a point-of-use model, which is inserted directly into the cold or hot water line near your faucet or showerhead. A recirculating pump can be added to automatically feed cold water back into the heater, so you get instantaneous hot water without the wait.

A tankless water heater can be more costly than a standard tank model, but you’ll save money over time in your utility bills, repair and replacement costs, and space used by the unit. It’s important to consider your hot water usage habits when selecting a size of tankless heater for your home.

One drawback of a tankless water heater is that the hottest water can take longer to reach your faucet, because it takes seconds for cold water to travel to the hot water heater and then another few seconds for the heating element to turn on and raise the temperature. This is why many homeowners choose to install a recirculating system, which eliminates the waiting time and keeps your water at the desired temperature.

Like all appliances, tankless water heaters need routine maintenance. The heat exchanger must be flushed periodically to remove mineral deposits and keep the unit functioning properly. This is most necessary in hard-water areas. You should have your unit flushed every three to five years, or more often if you live in an area with high mineral content.

Condensing

Gas-fueled water heaters that employ condensing technology are 10 to 15% more energy efficient than conventional tank-type units. They extract the latent heat of vaporisation from the flue gases of combustion and preheat incoming cold water using this energy. This saves a lot of money and reduces greenhouse emissions. However, a water heater can only operate at its most efficient when return water temperatures are lower than the vaporisation point.

In a non-condensing unit, most of the heat created from the combustion process is vented out into the atmosphere. The rest is used to heat the water, but it creates a hot exhaust gas that requires metal venting, usually stainless steel or thick aluminum. Condensing units, on the other hand, extract additional heat from these gaseous byproducts and use it to further heat the water in a secondary heat exchanger.

The combustion process produces gaseous byproducts like steam, carbon dioxide and other impurities that need to be vented out. A non-condensing unit releases all of these byproducts into the atmosphere, but a condensing water heater uses them to help pre-heat the incoming cold water. This saves a considerable amount of energy and reduces carbon dioxide emissions.

A condensing unit is designed with a second heat exchanger, in addition to the standard primary one found on every continuous flow water heater. The new heat exchanger helps extract more heat from the flue gases and converts it into additional hot water that is then used to preheat the incoming cold water.

When comparing these two types of water heaters, it is important to know which efficiency ratings are being used. Non-condensing units are typically rated using Gross calorific values, while condensing models use Net calorific values. Net calorific values take into account the water heating efficiency of the appliance as well as its thermal efficiency.

When deciding which type of water heater to purchase, consider your priorities and budget. If you prioritize energy efficiency and minimizing environmental impact, then a condensing tankless water heater is the right choice for your home. However, if you are concerned about initial investment and want more flexibility with installation location, then a non-condensing model might suit your needs better.

Installation

A conventional tank-type water heater is a heavy metal container that holds 40 to 60 gallons (151 to 227 liters) at 50 to 100 pounds per square inch (PSI). A metal insulating blanket covers the interior of the tank. Water enters through a dip tube at the top of the tank and exits through a drain valve near the bottom. It is heated as it flows through the tank. Most tanks have a temperature and pressure relief valve located on the side of the tank. This valve is used to prevent the tank from overheating and protects the home from damage. It is a good idea to check the valve regularly and clean it as needed.

The new water heater will need to have a drain connected to it, so a suitable location needs to be selected. It is important that the drain line be properly routed to avoid a clog. The new water heater also needs a vent pipe to release combustion gases out of the house. The venting pipe should be properly routed, as well.

Water heaters are heavy, so it’s best if you have help when moving and installing them. If you don’t, it’s possible for back injuries to occur. Also, always use a dolly when removing and lifting water heaters.

Once the old water heater is removed, install the new one. Connect the electrical wires and gas lines according to the manufacturer’s instructions. Be sure to follow the wiring diagrams closely and only use licensed plumbers for this task. Different electric heaters have very different configurations and colors of the wires, and you could get seriously electrocuted if you try to do it yourself.

Before connecting the new temperature and pressure relief valve, buy a tube of copper tubing and measure the distance from the bottom of the valve to the floor place. Cut the tube to this length and solder a male adapter to one end. Cover the adapter threads with Teflon tape and screw the valve in the tank, making sure that it is positioned with its opening pointing down.