HPAC 2021: Our Monthly Quiz

The heating, piping, and air conditioning industry has been a fixture of ‘civilized’ life on Planet Earth for well over a century, and the focus of this venerable publication since 1929. The inventive and problem-solving work of engineers, manufacturers, and building owners have continuously helped to expand the impact of the HVACR industry beyond creature comforts and food and data storage to life and death issues like greenhouse gas reductions and, especially today, virus mitigation.

 

With all that in mind, HPAC Engineering here welcomes you to join us on a fun monthly ride through the milestones, innovations, people, places, problems and products that have come to define this industry and your work. Hopefully, there may even be a chuckle or two along the way. So, here goes, and see below for your chances to win a $50 Amazon gift card.

Photo Credit: JW Associates

With an assist from Honolulu-based test prep service Engineering Pro Guides, here are five problems to kickstart the fall term. 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

Photo credit: iStock
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

Photo credit: Daikin Applied
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

Photo credit: Sika

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

Photo credit: Comfort Zone Heating & Cooling

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

Photo credit: Dreamstime