Interior Design Fittings and Fixtures - Plumbing

Plumbing Fixtures Continued

Induced Siphonage

Induced Siphonage is the loss of water from a trap caused by a reduction in pressure at the outlet of the trap. This condition is normally caused by flow from fixtures connected to the same pipe but at a higher level. Negative pressure is created in the pipe from the excessive flow from a higher fixture. Think of siphonage, as a form of suction or a common example is the pressure used to siphon fuel from the petrol tank of a car.

Self-Siphonage

Self siphonage is similar but caused by the long leg of the pipe being long enough to create a suction or siphon. The actual air pressure being greater than the pressure in the pipe essentially causes the siphon effect. When the pipe is full of fluid and moving, there is no compensating air, then the water seal will get sucked, pushed or siphoned into the waste pipe. There are now self-venting traps that allow air into the system to stop the siphoning effects.

Vents

These are the items that allow air into the system to balance and stop the water seals from siphoning themselves out and allowing noxious gas into the living areas. They eliminate the positive and negative pressures exerted by fluid flowing in the pipes. Other benefits that vents provide are reducing the corrosive gases on metal piping and letting foul gases out of the system.

Wash Down Pan

This is the most common of toilet pans. It has a wash down pattern and eliminates all waste or cleans all waste from the pan by using free falling water to run around the rim and clean the pan. The weight or force of the water also forces all the waste through the water seal and into the soil pipe while the last of the water from the flush reseals the water seal. The full flush was once 11 litres but has now been reduced to between 6 and 3 litres, which is a consideration when specifying pans as an interior designer.

Pan Connector

This is the pipe connection between the soil pipe and the pan. This is normally by means of a large rubber ring connecting the pipe to the pan and the other end is connected to the soil pipe.

Cistern

This is the tank above the pan that holds the water to flush the pan. It is controlled by a button or lever to allow the flow of the water which enables flushing. It is refilled by a water feed pipe that's inlet valve is opened when the water is emptied from the cistern. A lever supported by a floating ball (called a ball cock) opens and closes the valve according to the cistern being empty or full.

Air Gap

This is a gap at the top of the cistern to prevent any water from the cistern (which is part of the soil fixture and therefore subject to contamination from bacteria) reentering the water supply by siphoning.

Isolating Valve

As the name implies this is a valve to isolate one part of the water system from the rest of the reticulation. This allows the system to be worked on without water pouring out of that part of the system. It is similar to a stop valve.