Refrigeration and Air Conditioning
The leaks in a refrigeration system using Freon are detected by

Smelling
Using reagents
Halide torch which on detection produces greenish flame lighting
Sulphur sticks which on detection gives white smoke

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Refrigeration and Air Conditioning
The C.O.P. of an absorption type refrigerator is given by (where T₁ = Temperature at which the working substance receives heat, T₂ = Temperature of cooling water, and T₃ = Evaporator temperature)

[T₃ (T₁ - T₂)]/ [T₁ (T₂ - T₃)]
[T₁ (T₁ - T₂)] / [T₃ (T₂ - T₃)]
[T₃ (T₂ - T₃)] / [T₁ (T₁ - T₂)]
[T₁ (T₂ - T₃)] / [T₃ (T₁ - T₂)]

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