Question 143Refrigeration/AC - 1st Asst/Chief70% to pass
Which of the following is true concerning the class "A" air conditioning system shown in the illustration as used to condition the air of large public spaces? Illustration GS-RA-09
AI Explanation
The correct answer is C: The dry bulb room temperature is controlled by a steam heated reheater and its associated pneumatic control valve.
This is correct because in a Class "A" air conditioning system used to condition large public spaces, the dry bulb temperature of the space is controlled by a steam heated reheater. The reheater, and its associated control valve, are used to reheat the air after it has passed through the cooling coil, allowing precise temperature control of the space.
The other options are incorrect - A is incorrect because the preheater steam flow is typically controlled by a separate thermostat, not the space thermostat. B is incorrect because the cooling coil and reheater can be used simultaneously to provide precise temperature control. D is incorrect because the reheater is used even when in the cooling mode, to provide the final temperature adjustment.
Related Questions
#141 For the proper control of the air temperature in an air conditioning system using chilled water circulation, which of the listed conditions should remain constant regardless of load changes? #142 Which of the processes listed would be the most satisfactory method to use to lower the humidity of the air being circulated by an air conditioning system? #144 Which of the following is true concerning the class "D" air conditioning system shown in the following illustration? Illustration GS-RA-42 #145 A room humidistat initiates the lowering of the humidity of the conditioned supply air to a space, while the actual process is accomplished by what means? #146 To prevent the unnecessary loading of an air conditioning system while maintaining the designed dry bulb temperature and relative humidity in an air conditioning system, what should be done?