Plumbing Systems – Water
Plumbing Systems – Getting Water Into the House
This incorporates getting the water into the house or building either as a direct or indirect feed. Directly from the main supply into the system (also known as a high pressure system) or to indirectly fill a water holding tank (to lower the pressure in the system and known as a low pressure system), which in turn feeds into the building or house.
Once in the building (the pipes) the water under pressure is released directly to the cold taps and toilet cistern and also to the hot water cylinder, which in turn feeds to the hot water taps.
To simplify it, if the water enters directly into the system from the mains supply it is called a high-pressure system, if it goes through a holding tank it is a low-pressure system.
So why do we have the two plumbing systems for getting water into the house?
Both plumbing systems in different circumstances produce our desired results which is getting water to our taps, but depending on the amount of pressure that feeds the water into the building determines if it is a high or low-pressure system. A low-pressure system will have a holding tank in the ceiling to contain the water from the mains or from an alternative water supply. That is why we need to have two different types of plumbing fittings to cope with the different levels of water pressure.
There are two reasons why a low-pressure system may be in place.
1) The system is old and not able to take the pressure of the water main even through a pressure reducing valve.
2) Or the water feed is slow without much pressure at the source, so a holding tank and header pipe are used to create enough pressure for the system to work effectively.
Today most new systems are high pressure, as the modern fittings and pressure reducing valves are able to cope with the mains pressure.
This also means that items such as hot water cylinders are able to cope with the pressure and consequently the shower that you receive is no longer a dribble.