# Mechanical Engineering - Heat Transfer, Refrigeration and Air Conditioning - Discussion

Discussion Forum : Heat Transfer, Refrigeration and Air Conditioning - Section 6 (Q.No. 1)
1.
A condenser of refrigeration system rejects heat at the rate of 120 kW, while its compressor consumes a power of 30 kW. The coefficient of performance of the system will be
1/4
1/3
3
4
Explanation:
No answer description is available. Let's discuss.
Discussion:
25 comments Page 1 of 3.

Pratheesh said:   4 years ago
(1)

Amaan Sayyed said:   4 years ago
120/30=4 this is the right answer.

Vinay BEL said:   4 years ago
120 - 30 = 90.
(1)

Kajal Patil said:   4 years ago
(2)

Swapnil Shelke said:   4 years ago
I also agree with the answer 3 as here COP of the refrigeration system is asked clearly here REFRIGERATING EFFECT is 90 and work input 30.
(1)

S Kamran said:   5 years ago

120kw is heat rejected(not R.E)by the condenser that heat is the sum of Refrigeration effect(R.E)& The heat added by compressor work.. & COP= R.E/Work Input. So the final answer will be COP=(120-30)/30=3.
(1)

Swagat said:   5 years ago
COP = (120-30)/30.
= 3.
(2)

Zeeshan said:   5 years ago
Point to ponder is whether the COP of the heat pump is asked or COP of the Refrigeration system. The question doesn't define the fact categorically. Assuming heat pump answer is 4, of we assume COP of refrigeration system then given answer is wrong and it must be 3.

Vishnu said:   6 years ago