What Are the Two Subsystems in Your Home Plumbing?


The two subsystems in your home plumbing are freshwater and wastewater subsystems. Basically, as the names indicate, one subsystem brings freshwater into the house and the other removes the drain water out of the house. A lot of people don’t try to understand their plumbing system till there is some sort of a problem.

Learning about it is not just a great way to stay ahead of the curve but is also a money saver. It will give you the ability to take on little repairs around the house without having to call a handyman every single time. So, let’s jump right in.

Types of Plumbing Systems

The two major types of plumbing subsystems are a part of the larger plumbing network of the house. But mostly, they work without any overlap. There are connections between the two but it is indirect.

Freshwater or Water Supply

This is the first subsystem that brings water into the house from a main water supply. You use different types of pipes and shut-off valves to regulate the water entering your home.

When dealing with heating and cooling systems, you will also need to know a thing or two about temperature control. And since at least some of this will be drinking water, you must also make yourself aware of purification systems.

Now, once water enters the system, it gets distributed to different parts of the entire plumbing system moving through the many valves and pipes. This movement is made possible due to the pressure in the water.

Through these pipes it enters different spots in the house like showers, sinks, washing machines etc. And depending on your requirements, some or all of them are equipped to deal with hot and cold temperatures.

And when that is the case, it is the job of the supply line to carry clean water from the water tank to the heater or boiler and finally to the outlet of your choice in bathrooms, kitchens and what else you may have.

The system also has a shut-off valve that can stop all water supply in an emergency situation. If you don’t use it, there will be a burst pipe and water leaks into the house with a vengeful speed.

This valve might be linked to individual water supply systems or the whole plumbing system. Individual shut-off valves are helpful if the problem is confined to a particular faucet or sink.

The force within the pipes will make the water move from the water tank towards any specific outlet. Now, this does not take a lot of work. But when you need water to be pumped back into the water tank (especially those that are located on the rooftop), it will be going against gravity which means you need a motor to push the water up. This particular subsystem is usually made of copper, polybutylene or PEX pipes.

Wastewater or Drainage System

The second part of your home plumbing subsystem is the one that literally takes the trash out. This is the wastewater system and it is not connected to your supply system.

That means it does not count on any kind of pressure to get the drainage water out of your home. What it does use is gravity which is why the pipes are angled downwards and that helps the water escape comfortably.

There will also be a few vents in the system through which air is delivered to the wastewater system. With this air supply and gravity systems in place, the wastewater goes into the septic or sewer tank. And from there it goes into the sewage treatment plant in your region.

The vents are typically located on your rooftop where the air enters the system. In their absence, the water flow in the pipes will get interrupted and will then need to be diverted manually.

Vents also have another function. The dirty water that is the result of using clean water has a lot of waste and also releases toxic gases. These gases exit the system using the vents present on the rooftop.

This keeps bad odors and also helps avoid health risks. And all of this can be jeopardized with a clogged drain. So, it is important to make sure the drains are unclogged so that both the water and the toxic gases can leave your plumbing system with ease.

How the System as a Whole Works

It is clear by now that the pipes, joints and fixtures are a very important part of the whole home plumbing system. Keeping them clean is key to having a healthy system.

Now, if there is a problem in the supply line or the drainage system or the vents you will have a problem with the entire system even though the incoming and outgoing lines are not directly connected.

The vent pipes, it is now clear, are connected to the wastewater pipes and hence their performance depends on each other. But here’s how the overall movement takes place in the plumbing system.

When the water enters your plumbing system through the main line, there is often a meter that registers the amount of water that is being used. The shut-off valve which you will use in the event is located near this water meter.

Pro Tip: If you are trying to locate the main water line of a new house, getting close to the water meter is a great first step.

Parting Thoughts

It is good to know all these things if you are a DIY-er. But the information also comes in handy when you are hiring a licensed plumber. This is also because they are bound to state and local laws that will keep you out of trouble and also keep your system safe.

It is also helpful if you ever try to sell the house because you will not be in violation of any plumbing codes.

Professional plumbers are also fairly aware of changes in technology. This makes them better equipped at providing you with the best possible solution to the problem at hand.

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