HVAC BOMA 501
1. Dual Duct SystemANS
A system in which hot air and cold air are supplied by separate ducts and mixed at each controlled space to provide
the desired supply air temperature. This method consumes a great deal of energy.
2. Muiltizone SystemANS
an a/c system in which the zone control is obtained by mixing hot and cold air at the unit in response to a room
thermostat
3. Load CalulationsANS
take the sensible heat and the latent heat into consideration
4. which of the following does not provide sensible heat gain?ANS
Heat from cooking or hot baths (latent heat has to do with moisture)
5. Which of the following is the way that solar radiation disperses in a build- ing?ANS
Transmitted directly to the interior of the building, absorbs by glass, reflected into the building
6. outside air may get into the air conditioning spaces by...ANS
infiltration through the walls, infiltration through the swinging doors, air induced by replaced exhaust
7. In commercial buildings heat generated by lights does not seriously affect the control of the heating
systemANS
false
8. the human body's feeling of well being depends upon....ANS
The body's metab- olism
9. which of the following natural laws has the greatest bearing on the science of air conditioning?ANS
Boyles' Law, Charles' Law, Dalton's Law
10. Why is a pitch pocket commonly used?ANS
To protect the piping and seal the roof from refrigeration lines passing through it
11. Which of the following is an evaporative type condenser and what governs its cooling?ANS
a cooling tower governed by web bulb temperature
12. on an evaporative condenser what is the purpose of the eliminatorANS
to separate the moisture carry over
13. specific heat of a substanceANS
the amount of heat necessary to raise the temperature of one pound of a substance one degree Fahrenheit
14. Latent HeatANS
the amount of heat necessary to change a liquid to a vapor with no change in temperature
15. The difference between a pump, a fan and a compressor is. ......................................................... pumps pump
liquid, fans and compressors pump air
16. Which of the following checks should be made of a blower-drive?ANS
Check the blower belts for cracks and wear, check the motor bearings for wear, check the blower bearings for wear
17. Which of the following is a good rule to follow when checking air filters?ANS
air filters should be of the size and type recommended by the equipment manufacturer
18. When one of the three phases of a motor fails, how will the motor react?ANS
A winding will run hotter, the motor will (generally) not start, the two phases will draw
1.5 (1 1/2) times more current
1/8
, HVAC BOMA 501
19. When megohming a motor winding what is the rule of thumb to find an acceptable range of resistance
to ground?ANS
1000 ohms/volt
20. Which of the following may be the cause of improper air distribution?ANS
High pressure drop thru ducts and fittings, dirty filters, incorrect fan speeds
21. Friction losses of pressure in ducted systems occur.....ANS
in elbows, along duct walls, with increase in air speed
22. Which of the following may cause faulty fan operation?ANS
Loose belt drive, restricted air intake, improper fan bearing lubrication
23. What is the first step taken in all troubleshooting processes?ANS
Analyze the complaint
24. If the complaint is 'too little heat' and the burner is short-cycling the most likely cause is....ANS
the thermostat is out of adjustment
25. Excessive combustion noise is most likely caused by....ANS
improper burner adjustment
26. When a complaint is "too much heat" and the burner is continuously running the most likely cause
is....ANS
faulty wiring
27. In a case of failure of a burner to start the most likely cause is....ANS
a blown fuse
28. what is the most probable cause of a burner to not start?ANS
power failure
29. when the complaint is 'too much heat' and the heat element operates continuously the most likely
cause is....ANS
faulty control wiring
30. if the complaint is 'too much heat' and the electrical wiring is short-cycling the most likely cause is...ANS
the thermostat heat anticipator is set too low
31. In case of an electrical heating system not starting, the most likely cause is...ANS
a blown fuse
32. A psychrometric chart is a graph representation of...ANS
thermodynamic prop- erties
33. Heat flows in one direction usually from....ANS
a position of higher temperature to a position of lower temperature
34. the three main ways heat transfer takes place are...ANS
convection, conduction, radiation
35. which of the following material is the best conductor of heat?ANS
metal
36. heat will continue to flow between two bodies until they are the same....ANS
-
temperature
37. enthalpy refers to...ANS
heat content of a refrigerant (both latent AND sensible)
38. Psychometric is the science of dealing with the relationship between...ANS
-
2/8
1. Dual Duct SystemANS
A system in which hot air and cold air are supplied by separate ducts and mixed at each controlled space to provide
the desired supply air temperature. This method consumes a great deal of energy.
2. Muiltizone SystemANS
an a/c system in which the zone control is obtained by mixing hot and cold air at the unit in response to a room
thermostat
3. Load CalulationsANS
take the sensible heat and the latent heat into consideration
4. which of the following does not provide sensible heat gain?ANS
Heat from cooking or hot baths (latent heat has to do with moisture)
5. Which of the following is the way that solar radiation disperses in a build- ing?ANS
Transmitted directly to the interior of the building, absorbs by glass, reflected into the building
6. outside air may get into the air conditioning spaces by...ANS
infiltration through the walls, infiltration through the swinging doors, air induced by replaced exhaust
7. In commercial buildings heat generated by lights does not seriously affect the control of the heating
systemANS
false
8. the human body's feeling of well being depends upon....ANS
The body's metab- olism
9. which of the following natural laws has the greatest bearing on the science of air conditioning?ANS
Boyles' Law, Charles' Law, Dalton's Law
10. Why is a pitch pocket commonly used?ANS
To protect the piping and seal the roof from refrigeration lines passing through it
11. Which of the following is an evaporative type condenser and what governs its cooling?ANS
a cooling tower governed by web bulb temperature
12. on an evaporative condenser what is the purpose of the eliminatorANS
to separate the moisture carry over
13. specific heat of a substanceANS
the amount of heat necessary to raise the temperature of one pound of a substance one degree Fahrenheit
14. Latent HeatANS
the amount of heat necessary to change a liquid to a vapor with no change in temperature
15. The difference between a pump, a fan and a compressor is. ......................................................... pumps pump
liquid, fans and compressors pump air
16. Which of the following checks should be made of a blower-drive?ANS
Check the blower belts for cracks and wear, check the motor bearings for wear, check the blower bearings for wear
17. Which of the following is a good rule to follow when checking air filters?ANS
air filters should be of the size and type recommended by the equipment manufacturer
18. When one of the three phases of a motor fails, how will the motor react?ANS
A winding will run hotter, the motor will (generally) not start, the two phases will draw
1.5 (1 1/2) times more current
1/8
, HVAC BOMA 501
19. When megohming a motor winding what is the rule of thumb to find an acceptable range of resistance
to ground?ANS
1000 ohms/volt
20. Which of the following may be the cause of improper air distribution?ANS
High pressure drop thru ducts and fittings, dirty filters, incorrect fan speeds
21. Friction losses of pressure in ducted systems occur.....ANS
in elbows, along duct walls, with increase in air speed
22. Which of the following may cause faulty fan operation?ANS
Loose belt drive, restricted air intake, improper fan bearing lubrication
23. What is the first step taken in all troubleshooting processes?ANS
Analyze the complaint
24. If the complaint is 'too little heat' and the burner is short-cycling the most likely cause is....ANS
the thermostat is out of adjustment
25. Excessive combustion noise is most likely caused by....ANS
improper burner adjustment
26. When a complaint is "too much heat" and the burner is continuously running the most likely cause
is....ANS
faulty wiring
27. In a case of failure of a burner to start the most likely cause is....ANS
a blown fuse
28. what is the most probable cause of a burner to not start?ANS
power failure
29. when the complaint is 'too much heat' and the heat element operates continuously the most likely
cause is....ANS
faulty control wiring
30. if the complaint is 'too much heat' and the electrical wiring is short-cycling the most likely cause is...ANS
the thermostat heat anticipator is set too low
31. In case of an electrical heating system not starting, the most likely cause is...ANS
a blown fuse
32. A psychrometric chart is a graph representation of...ANS
thermodynamic prop- erties
33. Heat flows in one direction usually from....ANS
a position of higher temperature to a position of lower temperature
34. the three main ways heat transfer takes place are...ANS
convection, conduction, radiation
35. which of the following material is the best conductor of heat?ANS
metal
36. heat will continue to flow between two bodies until they are the same....ANS
-
temperature
37. enthalpy refers to...ANS
heat content of a refrigerant (both latent AND sensible)
38. Psychometric is the science of dealing with the relationship between...ANS
-
2/8
