How Drainage System Works
Drainage starts from the time water gets into the house to the point where it is drained off.
A good drainage system ensures that water reach its point of use and after that it is drained in an appropriate manner. The plumber ensures that water is conveyed to all parts of the building where it is required.
Careful design and choice of material ensure the water is not polluted.
Fresh, clean water which is under pressure is directed to the house by a service pipe or other source of water. The water is supplied around the house through a network of branch pipes of various dimensions. The largest has 19mm diameter and the smallest 9.5mm usually for the toilet faucet. For ease of individual repair, a shutoff valve is placed near each fixture and faucet.
A separate branch for hot water supply is also available complete with a shutoff valve. The tank is fitted with a drain valve for cleaning or repair purposes.
Hot water is supplied to the necessary areas in the same way as cold water. The tank is fitted with a thermostat to regulate temperature. In case the thermostat is faulty, the tank is fitted with an emergency valve that auto open to release overheated water, preventing the water from boiling and the tank from exploding.
Once water is used, it is directed to the sewer system efficiently and hygienically. The flow of drainage is dependent upon gravity and thus pipes have a bigger diameter than supply pipes. The soil pipe which serves the toilet is the largest with a diameter of 7.5 to 10Cm. The pipes also run downward at an angle to assist in water flow. Each connection is fitted with a trap which is U-shaped or P-shaped fitting that allows easy flow of water. The trap maintains a small amount of water that prevent noxious gases from seeping into the atmosphere.
From the trap, sewer flows into the main stack that leads to the main branch. The main stack has an opening at the roof top to allow noxious gases to escape and also provide air flow throughout the drainage system.