An office for seating 30 occupants is to be maintained at 22°C DB and 55% RH. The outdoor conditions are 36°C DB and 27°C WB. The various loads in the office are: Solar heat gain = 8,500W; Sensible heat gain per occupants = 83 W; Latent heat gain per occupant = 100W; Lighting load = 2,500W; Sensible heat load from other sources = 12,000W; and Infiltration load = 15 m3/min. Assuming 40% fresh air and 60% of recirculated air passing through the evaporator coil and the by-pass factor of 0.12, determine the following: A) The Dew Point Temperature of the coil, in degrees Centigrade. B) The Capacity of the Airconditioning Plant, in Tons of Refrigeration.

An office for seating 30 occupants is to be maintained at 22°C DB and 55% RH. The outdoor conditions are 36°C DB and 27°C WB. The various loads in the office are: Solar heat gain = 8,500W; Sensible heat gain per occupants = 83 W; Latent heat gain per occupant = 100W; Lighting load = 2,500W; Sensible heat load from other sources = 12,000W; and Infiltration load = 15 m3/min. Assuming 40% fresh air and 60% of recirculated air passing through the evaporator coil and the by-pass factor of 0.12, determine the following: A) The Dew Point Temperature of the coil, in degrees Centigrade. B) The Capacity of the Airconditioning Plant, in Tons of Refrigeration.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.46P

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An office for seating 30 occupants is to maintained at 220C DBT and 55% RH. The outdoor conditions are 360C DBT and 270C WBT. The various loads in the office are: Solar heat gain = 8500 W, Sensible heat gain per occupant = 83 W, Latent heat gain per = occupant = 100 W, Lighting load = 2500 W, Sensible heat load from other sources= 12000 W, Air infiltration 15m3/min. Assuming 40 % fresh air and 60% recirculated air passing through the evaporator coil and the by pass factor of 0.12, Determine:-i) Dew point temperature of the coil, ii) Capacity of the plant.
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