Skip to content

How Does A Water Heater Work?

Water heaters may look like big, complex pieces of machinery, but they are not difficult to understand. These usually look like large cylinders, and the unit is installed in the basement or laundry room. Some have tanks while newer models don’t, but the old reliable tank heater is predominantly used in the US today.

It’s a pretty essential appliance. The water heater is a drum filled with water that is heated using a heating mechanism on the side or at the bottom of the appliance. Don’t let the simple shape fool you, though. Water heaters boast an ingenious design and mechanism.

What You Will Find Inside Your Water Heater

To understand how your water heater works, you need to understand the components that heat your bath and sink water:

The Tank

The tank comprises of several layers, and each one has a purpose. For example, the inner one is lined with protective glass and can contain 40 gallons of water or more. The outer layer is covered with material that acts as an insulator, and on top of that is another insulating layer that keeps the heated water hot.

The Shut-Off Valve

The shut-off valve blocks water from flowing back into the heater. It can be found above the unit.

Hot Supply

This can be found inside the tank right at the top. It allows hot water to flow out of the tank, through the pipes and into your shower or whatever appliance you need it for.

The Thermostat

The thermostat helps users control the temperature of the water in the tank. You can adjust it to meet your temperature requirements .

The Dip Tube

The dip tube is on top of the tank. It goes into the tank, right into the bottom, where the water is heated. It’s where the water enters the tank to replenish the dwindling supply of hot water as you bathe, wash dishes, do laundry, etc.

The Drain and Pressure Relief Valve

The drain valve allows you to empty the tank quickly, and it is located at the bottom. The pressure relief valve maintains the water pressure in the tank within safe limits.

Anode Rod

The anode rod prevents the tank from rusting. It attracts all corrosive minerals in the water (effectively ‘sacrificing’ itself), so the tank remains undamaged. The rod is made of aluminium, and its core is made of steel. Make sure that you replace it every three to five years or so, depending on the hardness of your water supply.

The Gas Valve

Also known as the burner assembly – the gas valve maintains a flame under the tank, which heats the water. A heating element does this in an electric water heater.

How A Traditional Tank Warms Up Water

When water enters your home from the mainline, it splits into two separate pathways, and both make their way into your central intake system. The water doesn’t heat up immediately. When you turn on the hot water tap, cold water passes by the shut off valve and through the dip tube before entering the main tank.

The heating mechanism or gas valve maintains a flame at the bottom of the tank that heats the cold water as per your thermostat setting. The cold water goes to the bottom of the tank, and the heated water rises to the top.

When you turn on the hot water tap, more water enters the tank through the dip tube. Under a lot of pressure, the heated water at the top of the tank is displaced as new cold water enters it, and the former travels through the heat-out pipes to the tap.

How Your Tankless Water Heater Works

Tankless water heaters are growing in popularity and for a good reason. These can help you save money on your energy bill since they are designed to heat water only when it is needed. A flow sensor activates when you turn the tap for hot water. If the water heater is powered by gas, the sensor turns on a fan that draws in air, opens the gas valve, and ignites the burner.

In an electric unit, on the other hand, the sensor triggers an electric heating unit. In this case, a heat exchanger in the unit warms up, then heats the water to a set temperature. The hot water then flows into a tap directly.

Besides ensuring no energy is wasted to maintain a full water tank, tankless units are not limited by water supply. In other words, you will have all the hot water you need with a tankless unit. Hire professionals to replace your conventional gas heater with a tankless or an electrical one if you think the price is well worth the investment.

Contact Us

No one wants to shower in chilly water during the winter, but you won’t have much choice if your water heater gives up on you. If you think your unit is acting up, get in touch with us at King Heating, Cooling and Plumbing. We offer a wide range of plumbing services that can take care of all your plumbing issues.

Get started by contacting us for a FREE inspection of your unit. From hidden leaks to faulty gas valves, our trained and professional plumbers can handle any issue. Our services are available 24/7, so rest assured, we will be there when you need us. We also provide water heater maintenance services which include yearly flushes and safety checks. Allow our team to help you with your unit’s upkeep. It will surely last for years to come.