3.1 Identify the water trap above - NSC Civil Technology Construction - Question 3 - 2017 - Paper 1

The primary purpose of a water trap is to prevent sewer gas, which can be harmful, from flowing back into the building through plumbing fixtures. It does this by maintaining a water seal that blocks these gases.

Two factors that determine the temperature of the water in a solar heater include:

1. The duration of sunshine, which affects the heat absorption by the solar panels.
2. The angle at which the solar panels are positioned, as this influences the amount of direct sunlight they receive.

The part in an electric geyser that is used to warm up water is called the heating element.

The cold water inlet is mounted at the bottom of the geyser to ensure that the incoming cold water does not mix with the hot water already present. This setup allows the heating element at the top of the geyser to heat the water efficiently, ensuring that hot water rises to the top and is available at the outlet.

The component installed for safety purposes to prevent the geyser from bursting due to excessive heat is known as a temperature and pressure relief valve.

The storm-water grid functions to collect and drain stormwater from roads, allowing water to flow off the roads and into the stormwater drainage system. This helps to prevent flooding and maintain road safety during heavy rainfall.

If the grid is blocked, one consequence is that stormwater will overflow onto the roads, potentially causing flooding and dangerous driving conditions.

Two mechanical methods that may be used to obtain water from a borehole include:

1. A wind pump, which uses wind energy to pump water from the borehole.
2. An electric pump, which relies on electricity to draw water from the borehole.

Draw a symbol for a fluorescent light at point A, typically represented as a straight line with two circles at the ends.

Draw a rectangular box to represent the distribution board at point B.

Draw a symbol for a double-pole one-way light switch at point C, usually represented as a circle with a line passing through it.

Indicate electrical wiring from C to A by drawing a line connecting the symbols at those points.

Draw the symbols for the indicated components, which include:

1. Rodding eye
2. Gully
3. Ventilation pipe
4. Branch pipes
5. Inspection eyes

Additionally, use abbreviations as required for the sewerage components.