Refrigeration And Air Conditioning - Study Mode
[#26] The leaks in a refrigeration system using Freon are detected by
Correct Answer
(A) Halide torch which on detection produces greenish flame lighting
Explanation
Solution: The leaks in a refrigeration system using Freon are detected by Halide torch which on detection produces greenish flame lighting
[#27] The higher temperature in vapour compression cycle occurs at
Correct Answer
(D) Compressor discharge
Explanation
Solution: The higher temperature in vapour compression cycle occurs at Compressor discharge
[#28] Highest temperature encountered in refrigeration cycle should be
Correct Answer
(D) Much below critical temperature
Explanation
Solution: Highest temperature encountered in refrigeration cycle should be Much below critical temperature
[#29] In actual air-conditioning applications for R-12 and R-22, and operating at a condenser temperature of 40°C and an evaporator temperature of 5°C, the heat rejection factor is about
Correct Answer
(B) 1.12
Explanation
Solution: T1 = 5°C or 273 + 5 = 278K T2 = 40°C or 273 + 40 = 313K $$eqalign{
& { ext{C}}{ ext{.O}}{ ext{.P}}{ ext{.}} = frac{{{ ext{T1}}}}{{{ ext{T2}} - { ext{T1}}}} cr
& = frac{{278}}{{313 - 278}} cr
& = frac{{278}}{{35}} cr
& { ext{C}}{ ext{.O}}{ ext{.P}}{ ext{.}} = 7.942 cr
& { ext{Heat rejection factor (HRF)}} cr
& = 1 + frac{1}{{{ ext{C}}{ ext{.O}}{ ext{.P}}{ ext{.}}}} cr
& = 1 + frac{1}{{7.942}} cr
& = frac{{8.942}}{{7.942}} cr
& = 1.12 cr} $$
[#30] The capillary tube is not used in large capacity refrigeration systems because
Correct Answer
(B) Capacity control is not possible
Explanation
Solution: The capillary tube is not used in large capacity refrigeration systems because Capacity control is not possible