Heating, Ventilation, Air Conditioning & Refrigeration (HVACR) SPPU Endsem Question Paper Nov 2025
All 8 questions from this SPPU endsem paper, as printed. Read them here or open the PDF.
- Subject code
- 402041
- Pattern
- 2019 pattern
- Exam
- Endsem
- Session
- Nov 2025
- Max. marks
- 70
- Time
- 2½ Hours
- Semester
- VII
- Paper code
- [6584]-217
Printed for: B.E. (Mechanical Engineering)
Instructions to the candidates
- Solve Q.1 or Q.2, Q.3 or Q.4, Q.5 or Q.6, Q.7or Q.8.
- Neat diagrams must be drawn wherever necessary.
- Figures to the right indicate full marks.
- Use of electronic pocket calculator is allowed.
- Assume suitable data, if necessary.
Questions
Q1
- a)[6]
Discuss any one method of capacity controls of reciprocating compressor.
Also asked:May 2025
- b)[5]
Explain with neat sketch of frost control circuit.
- c)[6]
Explain with neat sketch transcritical cycle.
OR- a)
Q2
- a)[6]
- b)[5]
Explain with sketch LP/HP cut-off.
- c)[6]
Q3
- a)[8]
- b)[10]
The atmospheric air at 30°C dry bulb temperature and 75% relative humidity enters a cooling coil at the rate of 200 m 3 /min. The coil dew point temperature is 14°C and the by-pass factor of the coil is 0.1. Determine: i) The temperature of air leaving the cooling coil ii) The capacity of the cooling coil in kW iii) The amount of water vapour removed per min, and iv) The sensible heat factor for the process 2
ORQ4
- a)[8]
Explain Thermal exchange of human body with Environment.
- b)[10]
The room sensible and latent heat loads for an air-conditioned space are 30 kW and 10 kW respectively. The room condition is 25°C dry bulb temperature and 50% relative humidity. The outdoor condition is 35°C dry bulb temperature and 60 % relative humidity. The ventilation requirement is such that on mass flow rate basis 20% of fresh air is introduced and 80% of supply air is recirculated. ADP of the cooling coil is 5°C. Determine: i) RSHF; ii) BPF of cooling coil; iii) supply air flow rate; iv) outside air sensible heat; v) outside air latent heat; vi) Capacity of cooling coil in TR
- a)
Q5
- a)[8]
Explain any four types of air distribution devices.
- b)[10]
A rectangular duct, 0.15 m× 0.12 m is 20m long and carries a standard air at the rate of 0.3m 3 /s having density 1.2 kg/m 3 . Calculate the total pressure required at inlet of the duct in order to maintain the flow and air power required. Take f =0.005.
OR- a)
Q6
- a)[8]
Explain fan laws and any two types of fans used in air distribution system.
Also asked:Nov 2022
- b)[10]
In the air duct system, as shown figure below, the branch BE is 20 m long and delivers air at 120 m 3 /min. The branch at CF is 15m long and delivers air at 140 m 3 /min. At the end D of the main duct, the air delivered is 220 m 3 /min. Take velocity in main duct AB is 600 m/min. Using a friction chart and equal pressure drop method, determine the diameter and velocity in AB, BC, CD, BE, CF Duct sections. Also calculate maximum pressure drop in the duct system. 3
- a)
Q7
- a)[6]
Explain with neat sketch, air water system.
- b)[6]
Write a short note on “Sorbents and Desiccants.
- c)[5]
OR- a)
Q8