Safe handling of refrigerants
1. State four handing safeguards, which must be practiced when dealing with refrigerants.
i. Safety glasses ii. Safety graves iii. Overall iv. Always ventilate the work area
2. Why should the air conditioner not be left switched on with the engine running for long periods?
A/C load requires a battery bank that may not be reasonable in size or cost so that the inverter is limited in application to available battery power.
3. If refrigerant contacts bare skin, what are the likely results and what first aid be provided?
We should be going to wash skin directly by clean water and go to see doctor.
4. What is ozone?
Ozone is a colorless odorless gas made of oxygen. Ozone is O3 - three oxygen atoms joined together
5. What type of radiation does ozone:
i. Prevent reaching the earth surface: UV, gamma ii. Reduce the level of that which reaches sea level:
Would only be about 3mm thick if brought down to sea-level
6. State the effects of releasing chorine based refrigerants into the atmosphere on:
It can destroy ozone that people could get serious problems such as skin cancer, damage eyes and throat.
ii. Marine organisms: contribute to atmospheric warming damages the atmospheric ozone layer helps filter out damaging ultraviolet radiation from the sun. The ozone layer acts like a giant sunshade that shields the earth from the sun's harmful ultraviolet radiation.
7. To what did nations agree with the montreal protocol:
They made an international treaty designed to protect the ozone layer by phasing out the production of numerous substances believed to be responsible for ozone depletion
8. What matters are covered in the “code of practice”? code of practice in australia that covered the control of refrigerant gases during manufacture, installation, servicing or de-commissioning of vehicle air conditioners.
9. Identify the components indicated in the diagram below.
i. Compressor ii. Condenser iii. TX valve iv. Evaporator
v. Receiver vi. Fan vii. Capillary tube
10. State the function of the following components
To pump the A/C system to keep the R134a and the lubricating oil circulating and to increase the refrigerant pressure and thus temperature. The internal design could be piston, scroll, and wobble plate, variable stroke or vane ii. Condenser: heat exchanger condensing efficiency will be compromised an increase of approximately 20% in high side head pressures is expected. an increase of 20% pressure means a 20% increase in temperature iii. Evaporator: the refrigerant to change from a low pressure cold liquid into a cold vapour. iv. Capillary tube/ bulb: a hollow tube filled with refrigerant, part of the thermostatic switch. Operates the switch or valve via temperature changes on the capillary tube, resulting in refrigerant expansion or contraction
v. TX valve:
The refrigerant enters the inlet and screen as a high-pressure liquid. The refrigerant flow is restricted by a metered orifice through which it must pass. As the refrigerant passes through this orifice, it changes from a high-pressure liquid to a low-pressure liquid (or passes from the high side to the low side of the system).
vi. Receiver driver: the receiver drier allows the passage of liquid refrigerant through it and into the