Does cold water go through the water heater, or is it available immediately to you? Learning how water moves through the pipes is important. Though the plumbing system is a bit complex, your life will be easier once you understand how the water pipes work.
Learning a few plumbing basics can be very helpful if you’re a homeowner. In this post, you’ll get to know how the water pipes manage to do the important job of bringing water to your faucet daily. So, are you ready to learn how water travels through your home? Let’s dive in.
How Does a Water Heater Work?
To understand whether water goes through the water heater, we must first understand how the water heater works. There are two types of heaters: gas and electric water heaters. The components of both heaters are almost the same, but the heating mechanism is different. These are the parts of a water heater:
Tank
Dip Tube
Heating Element/ Gas Burner
Thermostat
Valves
Heat-out Pipe
Water travels from the main line into the pipes in your home. Your home contains separate cold and hot water lines. Just before entering the water heater, the pipe splits into two pathways. The cold water lines are connected directly to all the faucets and fixtures in straight lines or at right angles.
The water that doesn’t go into the cold lines is emptied into the tank. The cold water is released to the bottom of the tank for heating.
On the other end of the process, the hot water reaches upwards towards the heat-out pipe. The heater’s heating element applies heat to the water and warms it up, and the cycle continues.
This hot water then enters the hot water lines that run parallel to the cold water lines. When you use the hot water tap, the hot water from the upper tank moves through the hot water lines and reaches the tap.
Does Cold Water Go Through Water Heater?
The main question is whether cold water goes through the water heater. The answer to this will largely depend on the type of water heater you’re using. The mechanism we explained above is for the tank water heater.
If it’s a tank water heater, the cold water doesn’t go through the water heater. Instead, the water goes to the tank, where the burner or heat exchanger heats it.
On the other hand, the cold water goes through the tankless water heater. Since there is no tank for heating or storing water, the cold water goes to the water heater directly. When you turn on the faucet, the cold water goes through the water heater and warms up. Then it goes into the hot water lines and reaches the taps.
Talking about the water lines, the cold water line doesn’t go through the water heater. This is true for any type of water heater, as the cold water lines are installed to slope away from the heater. They are installed in straight lines and reach directly to the faucets.
The hot water lines, on the other hand, go through the water heater. However, remember that the hot water lines contain cold water, too, before going into the water heater. The hot water lines from the water heater contain hot water that reaches the faucet.
Tank vs Tankless Water Heater
The main components of both types of tanks are the same, except the tank. The tank water heater has a tank that can store around 20 to 80 gallons of water. It is an insulated tank that keeps the water hot until it’s there.
The dip tube in the water heater takes cold water from the water lines and allows it to enter the tank. The heating of water is carried out using a heating element. When the water heats up, it is released through the heat-out pipe. The heat-out pipe is on top to release the hottest water into the hot water lines.
The tankless water heater is also called an on-demand water heater. It is compact and heats very fast. These water heaters heat water instantly, and you don’t have to wait for the heater to heat the water.
Tankless water heaters are becoming more common because of their quick heating mechanisms. These heaters heat the water based on gallons per minute. When hot water is not needed, the tank uses no energy. Hence, it is considered more energy-efficient. Though the initial cost is higher than tank water heaters, they help you save a lot on utility bills in the long run.
Tank Water Heater
Tankless Water Heater
Amount of water
Heats a large amount of water
Doesn’t heat a large amount of water
Heating time
Slow
Very Fast
Space
Big space required
Compact and can fit easily in narrow spaces
Installation
Inexpensive
Expensive
Energy efficiency
Higher electricity bills due to continuous heating
Energy efficient
Life
Shorter lifespan
Durable and long-lasting
People Also Ask
Does the Water Heater Affect Cold Water?
The cold water lines are completely separate from the hot water lines. The water running through the cold lines doesn’t enter the water heater. Thus, the water heater doesn’t affect the cold water in the cold water lines. It only heats the cold water coming to it through the hot water lines.
However, the water heater affects the water pressure for both the cold and the hot water. The water pressure decreases due to hard water buildup or the water heater valve.
Does Cold and Hot Water Run In the Same Pipes?
No, cold and hot water don’t run through the same pipes. There are separate water lines for cold and hot water. Every faucet or fixture has cold and hot water lines so the user can use either. However, some fixtures can have a single line, too, if only hot or cold water is needed there.
Where Does the Cold Water Go In a Water Heater?
The cold water coming through the hot water line enters the water heater through the dip tube. The dip tube extends to the bottom of the tank so that the cold water goes there and heats up. The cold water directly reaches the tank bottom, where there is the heating element. On the other hand, the hot water reaches upward towards the heat-out pipe.
Can Cold Water Enter the Hot Water Line?
Sometimes a plumbing disorder in the water lines can cause this issue. The hot and cold water lines are built separately, but they run close to each other in parallel lines. However, if the plumbing and installation of pipes are incorrect, the pipes might meet at a point. This can cause cold water to enter the hot water line. An incorrect mixing valve will lead to a crossover of hot and cold water and cause this issue.
Wrap Up!
Cold water goes into the water heater only when it flows through the hot water lines. The cold water lines are separate and don’t enter the water heater. In a household, both cold and hot water lines are necessary. Thus, they are installed separately. The cold water doesn’t mix with the hot water because it flows in a different direction. I hope that you now have the answer to your question: ‘Does cold water go through a water heater?”
Hi everyone! My name is Jason, and I am the founder of HeaterWise.com. Having run my own business as a Heating Engineer for 21 years, I have picked up a few things along the way.
I wanted to create Heater Wise as a place where anyone could come, from far and wide, to find the information that they need.
I hope you will join us here at Heater Wise, to get started on your own journey, to expand your knowledge, and make the best heating choices for you and your family.
