Refrigeration and Air Conditioning 3 E Part 1 doc

... Maintenance. Service. Fault-finding. Training 33 8 34 Efficiency and economy in operation 35 1 35 Catalogue selection 35 7 Appendix Units of measurement 36 7 References 36 9 Index 37 3 vi Contents The refrigeration ... space–temperature curves would eventually meet and no further heat could be trans- ferred. The fluid in Example 1. 11 would cool the water down to 3 C. The e...

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... condenser to re-heat, together with the energy supplied to the compressor and the fan motor (since the latter is in the airstream). Figures for this electrical energy will have to be determined and ... factor is therefore one of wet bulb rather than dry bulb temperature, and the closer the upper limits are approached, the less heat can be rejected and so the less work can be done. 23...

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... contributes CO 2 emission to the atmosphere. The choice of refrigerant is therefore about the efficiency of the refrigerant and the efficiency of the refrigeration system. The less the amount of energy ... these properties, and meets the new environmental requirements, but this chapter will show the developments that are taking place in influencing the selection and choice of a refri...

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... 11 .9 8.29 10 .7 8. 41 9.56 8.48 8.40 8.40 – 35 1. 63 15 .9 9.65 14 .5 9.92 13 . 1 10 .1 11. 9 10 .3 – 30 2.00 20.6 11 .0 19 .1 11. 5 17 .6 11 .6 15 .9 11 .9 Condensers and water towers 69 Hot gas Main condenser water Liquid Main condenser water Heat recovery circuit Example ... covered by the provisions of BS.4 434 :19 80 and require safety pressure relief devices as...

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... and shorten the working life. 11 .11 Site pressure safety tests Site-erected pipework, once complete, must be pressure tested for safety and freedom from leaks. Pressures will be 1 .3 times the 11 8 Refrigeration ... water cooling towers and evaporative condensers will permit their use elsewhere. Table 10 .2, based on the tentative temperature differences of 15 K and 12 K...

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... provide an insulated and refrigerated enclosure suitable for the handling and storage of perishable goods, at some predetermined temperature. The shape and size of the cold store will depend on: 1. ... in Figures 4 .18 and 13 . 2. Other types may have air- cooled or evaporative condensers, and so require refrigerant pipe connections on site to these condensers. Sizes range from 1...

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... plate freezers. Health and safety requirements continue to become stricter in the maintenance of the cold chain and the latest regulations should be adhered to. 17 8 Refrigeration and Air- Conditioning 15 .5 ... hygiene, or the cheese will be damaged. Some cheeses can be frozen for long-term storage, but must then be allowed to thaw out gradually and complete their ripening bef...

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... the doors, and such figures are based on observed practice. The parameters are the size of the store, the enthalpy difference between inside and outside air, and the usage of the doors. The latter ... their food reserves and then decaying [29, 33 , 34 ]. Table 21 .3 Product Temperature (°C) Heat of respiration (W/t) Apples 2 12 Pears 1 16 Bananas 13 48 Strawberries 0 45 Po...

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... connecting the inner and outer tappings to the ends of the manometer, the difference will be the velocity pressure. Figure 27.2 Vertical and inclined manometers Figure 27 .3 Pitot tube Sensitive and ... Reduce 900 × 600 – 1 .3 6.62 26 .3 0.04 1. 1 16 0.4 18 6.7 to 500 diameter 6 Fan 500 diameter – 1 .3 7 Enlarge 500 diameter to – 1 .3 3. 61 7.8 0.4 3. 1 34 .1 26 .3 60...

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... in the UK at the present time is where air cooling is required in the summer and air heating from the same piece of equipment in the winter. The alternatives will be electric resistance heating, ... plantroom and possible refrigerant leaks. Steam drives have also been used. The economics of the heat pump are dependent on the relative costs of the drive power and heat energy from oth...

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