Download HVAC Exam 1: Questions and Answers for Test Preparation and more Exams Engineering in PDF only on Docsity!
Matter exists in what three forms? - correct answer ✅solid, liquid, gas What is temperature measured by? Quantity or intensity - correct answer ✅Intensity Define British thermal unit (Btu) - correct answer ✅Measure of heat energy - amount of energy needed to raise 1 lb of water 1 degree F How much heat is required to raise the temp of 100 lb or water from 70F to 120F - correct answer ✅Q=1000lb(1btu / change of temp) so 1000(1/ 50) = 50, If 750 Btu is supplied to 15lb of water at 72F what will be the resulting temperature? - correct answer ✅ 1 Btu raises air - correct answer ✅4.75F
To melt 1lb of ice you need - correct answer ✅144 Btu So to melt 2000 lbs of ice or 1 ton you need - correct answer ✅288,000 Btu What is 1 ton of refrigeration? - correct answer ✅288,000 Btu / 24 hrs = 12,000 Btu/Hr What is the hottest water can get? - correct answer ✅212F 1 Btu raises 1 lb of water - correct answer ✅1 degree F If 750 Btu is supplied to 15 lb. of water at 72F, what will be the resulting temperature? - correct answer ✅750/15=50F 50F + 72F = 122F Latent heat cannot be measured on a thermometer. True or false? - correct answer ✅True - only sensible heat can be
A ton of refrigerant is - correct answer ✅The amount of cooling a ton of ice can do in 24 hours 144 Btu = 1 lb of ice 2,000 lbs of ice (1 ton) = 288, 288,000 Btu / 24 hrs = 12,000 Btu/Hr It is desired to cool 25 gallons per minute (gpm) of water from 100F to 32F. How much refrigeration capacity will be needed? - correct answer ✅Q= 500 * gpm * Change in Temp Btu/hr for tons of refrigeration divide answer by 12, In changing 10 lbs. of water at 35F into ice at 32F, approximately how many Btu's of energy must be removed? - correct answer ✅First find 35F to 32F of water in Btu Then find 32F water to 32F ice in Btu then add the two so 10lbs changing 3 degrees = 30 Btu then 32F to 32F ice is 10*144 Btu = 1440 so 30 + 1440 = 1470 Btu
To change water to ice you need - correct answer ✅144 Btu / lb To change water to steam you need - correct answer ✅970 Btu / lb What does HVAC stand for? - correct answer ✅Heating, Ventilation and Air Conditioning ASHRAE stand for - correct answer ✅American Society of Heating, Refrigerating and Air Conditioning Engineers - Technical support and standards What does ACCA stand for? What is the role of ACCA in the HVAC industry? - correct answer ✅Air Conditioning Contractors of America - Trade organization, primarily educational
- What does AHRI stand for? What is the role of AHRI in the HVAC industry? -
Feet of water column is a measure of - correct answer ✅pressure Inches of water column is a measure of - correct answer ✅pressure 1 psi = 27.72" in water column PSIG is a measure of - correct answer ✅pressure What are the three modes of heat transfer? - correct answer ✅conduction, convection and radiation Under normal conditions, the heat your body produces is - correct answer ✅more than what your body needs The direction of heat flow is - correct answer ✅from warm to cold
The evaporation process cools because - correct answer ✅moisture while becoming vapor absorbs heat Humidity is a measure of - correct answer ✅moisture content Humidity is measured in - correct answer ✅grains of water vapor Air temperature, humidity, and air movement affect - correct answer ✅body comfort What is refrigeration? - correct answer ✅Refrigeration is the process of removing heat from where it's not needed and disposing of it where is it wanted or not objectionable What is a condenser? - correct answer ✅A condenser is a device for removing heat from a refrigeration system.
