Example (2): An air-conditioned auditorium is to be maintained at 27° db and 60% RH. The ambient condition is 40°C db and 30°C wb. The total sensible heat load is 100000 kJ/h and the total latent heat load is 40000 kJ/h. 60% return air is recirculated and mixed with 40% of make-up air after the cooling coil. The condition of air leaving the cooling coil is at 18°C. Determine: 1. Room sensible heat factor. 2. The condition of air entering the auditorium. 3. The amount of make-up air. 4. Apparatus dew point. 5. By pass factor of the cooling coil.

Example (2): An air-conditioned auditorium is to be maintained at 27° db and 60% RH. The ambient condition is 40°C db and 30°C wb. The total sensible heat load is 100000 kJ/h and the total latent heat load is 40000 kJ/h. 60% return air is recirculated and mixed with 40% of make-up air after the cooling coil. The condition of air leaving the cooling coil is at 18°C. Determine: 1. Room sensible heat factor. 2. The condition of air entering the auditorium. 3. The amount of make-up air. 4. Apparatus dew point. 5. By pass factor of the cooling coil.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter36: Refrigeration Applied To Air-conditioning

Section: Chapter Questions

Problem 8RQ: The most popular refrigerant used in the past for residential air-conditioning is R- ________.

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An air conditioning system is designed under the following conditions Outdoor conditions; 30°C dbt, 75% RH Required indoor conditions; 22°C dbt, 70% RH Amount of free air circulated; 3.33 m/sec Coil dew point temperature; 14°C The required condition is achieved first by cooling and dehumi dification and then by heating. Estimate (1) Capacity of cooling coil intons and its efficiency. (ii) Capacity of heating coil in kW. ii) Amount of water vapour removed kg/sec.
Question 4 A VRF cooling unit, having a cooling capacity of 25 kW, have the following COPS: COP100% = 369, COP75% = 5.72, COP50% = 6.65, COP25% = 8.16. Assume that the cooling unit has 13 hours of usage daily, having standby power of 200 W and energy tariffs of 41 cents per kWh. Using NEA's recommended AEC estimation, determine the annual energy cost up to 2 decimal points. Do not include "S" in your answer. Selected Answer: O 5,643.75 Correct Answer 5,584.12 0.01%
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