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Among these three different subsystems the waste drain and the vent pipes are interlinked with one another, that is, they affect the performance of each other and you cannot have one without having the other.Firstly lets take a look at the supply lines. The lines have the job of carrying clean hot and cold water from the boiler and the water tank at the rooftop respectively to the desired outlets present inside the home, like bathrooms, kitchen and any other place where there is a tap and water is needed. The water in these pipes moves under the force of pressure if the water is coming down from the tank present at the top, however, on the other hand, if the water is being pumped tothe tank from the bottom then the work is being done against gravity and this pumping pressure is created by the water motor which is responsible for filling the tank with clean water. This supply system is usually made of three kinds of pipes, namely, copper, PEX, PB.The second type of subsystem is the drainage system.
It is designed to carry the waste water from the toilets and sinks etc to the underground pipes of the home and then out to the public drainage lines. Water in these pipes flow under the effect of pressure and gravity when toilets operate, otherwise there is only the effect of the gravity which is responsible for the flow of the waste water. This system is made up of two types of pipes, CPVC or wrought iron.The third type of the plumbing system present in the home is the vent drains. These drains are present at the roof tops of the buildings and these are quite necessary for the drainage system to work properly as this plumbing system is responsible for the release of the toxic gasses from the drain pipe so that the pressure doesnt build up and hampers the flow of the waste water.These are the three different types of plumbing subsystem which work together to provide the user or the owner of the home with a good and efficient plumbing system.