HPAC 2023: Our September Quiz

Schools at every level have been reopening across the U.S. over the last few weeks. Now, as students, teachers and administrators return and adjust to a new climate for learning, let’s dust off the books to test your HVACR knowledge. With the assistance of Honolulu-based test prep service Engineering Pro Guides, here are five problems to kickstart the fall term.
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First off, a classroom of 24 students and one teacher has the following heat gains:

 

People: 250 Btu/h per person (Sensible); 200 Btu/h per person (Latent) 

 

Lighting: 4,000 Btu/h; Computers: 8,000 Btu/h; Walls, Roofs, Windows: 22,000 Btu/h 

 

Ventilation: 7,500 Btu/h (Sensible); 7,500 Btu/h (Latent) 

 

The air handler serving the classroom has a supply air temperature of 55 °F and the space is to be maintained at 75 °F DB and 50% Relative humidity. What CFM is required?

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2,675 CFM

2,790 CFM

3,865 CFM

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An air handler supplies 5,000 CFM at a temperature of 55 °F. The air handler was designed for 1,000 CFM of outside air at 87 °F DB and 78 °F WB. The remaining return air from the space is at 77 °F DB and 55% relative humidity. What are the entering conditions of the air into the coil, in DB and WB?
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79 ℉ DB, 59.6 ℉ WB

85 ℉ DB, 74.3 ℉ WB

85 ℉ DB, 75.7 ℉ WB

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The unit "clo" is used to describe the thermal insulation provided by which of the below items?

Wall insulation

Roof insulation

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Heating equipment insulation

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Which of the following codes are least likely to be required to be checked with regards to the installation of a commercial gas furnace?

NFPA 54

ASHRAE 90.1

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International Fuel Gas Code

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If you are designing an HVAC system at an elevation of 7,500 ft above sea level with outside air conditions of 60 F DB and 90% relative humidity, then what is the density and dew point of the outside air?

0.0631 lb/ft3 and 57.1 F dp

0.0631 lb/ft3 and 60.0 F dp

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0.0759 lb/ft3 and 55.1 F dp

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