Read the text and give a title

Change these words into another part of speech

Divide these sentences into three groups

Finish these sentences

1. Air conditioning implies...

a)...rapid loss of heat, b)...the transmission of energy in the form of waves, c)...provision for the expansion of the water, d)...the control of temperature, humidity, purity and motion of the air.

2. The purpose of ventilation is...

a)...to produce a desired temperature for maintaining comfort, b)...to supply heat for cooking and space heating, c)...to maintain air purity at an extremely high level, d)...to carry away excess heat and odors.

3. The basic pieces of air-conditioning equipment are...

a)...stokers, coal furnaces and boilers, b)...filters, preheat coils, humidifiers, reheat coils, fans and controls, c)...boilers and a system of pipes, d)...systems of steel and copper pipes.

A. Air Conditioning. B. Gas Supply. C. Ventilation.

1. Gas supply has come to be very widely used. 2. In industrial buildings three types of ventilation are in use so as to control dangerous gases and dusts. 3. In buildings such as homes, the leakage of air through cracks in doors and windows is usually sufficient. 4. As for the purpose air-conditioning system may be described as winter, summer and all-year. 5. The main utilization of natural gas is as a clean, convenient, economical source of heat. 6. Natural gas supply is used also as a heat source in commercial establishments. 7. Certain industrial process requirements and human comfort are the two major factors to be considered when designing air-conditioning system. 8. Air conditioning is meant for the control of temperature, humidity, purity and motion of the air in an enclosure. 9. The main purpose of ventilation is to carry away excess heat and odors.

Tasks before reading:

cycle, atmosphere, vary, proportion, phenomenon, reservoir, depression, classify, gravel, sanitary, domestic, standard, modern, location, protection, mineral, resources, flora, community.

One method of heating a building is to circulate hot water through radiators which are located in each room. The water is heated in a boiler by a burner and is kept at a constant temperature by a thermostat device called an aquastat. The aquastat is located on the outlet pipe from the boiler. The pipe runs in a continuous loop from the boiler to the radiators and back to the boiler. The function of a radiator is to transfer the heat from the hot water to the air in the room. Therefore they are made of a material which has the property of high thermal conductivity. The shape of the radiator is also important because the greater the surface area the more rapidly it gives off heat. One type of radiator, called a fin tube, consists of a number of thin fins shaped like a circle which are welded to a pipe passing through their centres. A thermostat in the room can be set to the required temperature. When the air temperature in the room decreases, the thermostat switches on the pump which is located on the return line from the radiators. When the room reaches the set temperature, the thermostat switches off the pump. An expansion tank is provided to allow for expansion of the water as it heats. A safety valve, located on the pipe leading to this tank, serves to relieve the pressure in the boiler if it is too high.

Make true statements by matching these halves of sentences:

a) When the pump is switched on

b) When the temperature of the water in the boiler decreases

c) When the temperature of the water in the boiler reaches the set temperature

d) When the air temperature decreases

e) When the radiator is turned on

f) When the water in the boiler expands

g) When the boiler pressure is too high

the aquast at shuts down the burner.

the safety valve relieves the pressure.

the thermostat switches on the burner.

it flows into the expansion tank.

the aquast at starts up the burner.

heat is transferred from the hot water to the air in the room,

hot water flows through the pipe to the radiators.

Дата добавления: 2014-10-15