A deep vacuum is an evacuation method in which a technician uses a vacuum pump (or the systems compressor) to pull a vacuum until no moisture or other
... [Show More] vapor remains in the system. If the compressor is used for this procedure, but CANNOT produce a deep vacuum, which of the following would be the problem?
A- Bad TXV
B- Low refrigerant
C- Leaky suction valve
D- Leaky exhaust valve
- What would be the minimum ventilation exhaust flow rate for a 1,000 Sq-ft darkroom? The ventilation system must be designed to supply the required rate of ventilation air continuously during the period the building is occupied "24/7".
A- 10,000 CFM
B- 1,000 CFM
C- 180 CFM
D- 120 CFM
Use a duct slide rule to determine required round steel duct size for a sheet metal duct system showing a pressure drop of 0.25 IWC, delivers 1,000CFM, has a total effective length of 263 feet, and a friction rate of 0.095 IWC/100.
A- 12 inch diameter
B- 10 inch diameter
C- 16 inch diameter
D- 14 inch diameter
What is the minimum required outdoor ventilation rate for a residence with three bedrooms, the bathrooms, one kitchen, and a 133 square foot one-car garage? (Assume continuous exhaust for kitchen and bathrooms.)
A- 115 CFM
B- 175 CFM
C- 225 CFM
D- 295 CFM
The Manual J specific heat formula used for changing the temperature is CFM=But/(1.08 x Change Temperature). Therefore, what would be the required heat input in BTUs to raise air quantity of 120CFM from the cold temperature of 30 dig F to a warm temperature of 80 dig F (without and altitude correction factor)?
A- 8573 But
B- 7824 But
C- 6660 But
D- 5231 B
According to OSHA, upper and lower guards shall be equipped on...
A- Grinding machines
B- Portable, power-driven circular saws
C- hand-fed crosscut table saws
D- hand-fed ripsaws
A standard sheet metal thickness gauge table will list the thickness of 24 gauge aluminum as 0.0201 inches, and the thickness of 26 gauge aluminum as 0.0159 inches (too thin). Correct multiple choice answer is 24 gauge aluminum ducts (0.0201 inches). In a residential building, the minimum wall thickness of an 8-inch round aluminum duct must be what minimum gauge thickness?
A- 24
B- 26
C- 28
D- 30
Carbon steel pipe with a wall thickness not less than __ shall be used for Group A1 refrigerant liquid lines 6 inches and smaller.
A- FMT
B- EMT
C- Schedule 40
D- Schedule 80
A plumbing vent outlet is discharging 2 feet above a forced- warm- air furnace outside air inlet. What is the minimum distance that the outside air inlet shall be from the vent outlet?
A- 12 feet
B- 20 feet
C- 15 feet
D- 10 feet
A contractor must build a 15,000 square foot educational auditorium. What would be the minimum outdoor ventilation in CFM?
A- 1,200CFM
B- 900CFM
C- 750CFM
D- 624CFM
Which of the following statements are true about the installation of vertical lifelines, independent support lines, and suspension ropes?
A- Must be attached to the same point on the scaffold
B- Must be attached independently of the scaffold
C- Must be attached to each other
D- Must be the same point of anchorage
The symbol "k" stands for the thermal transmission by conduction. Trying to solve for "k" for a 1 inch thickness of homogeneous material, the result will be measured in __\__.
A- (BTU)/(heft degrees F)
B- (square foot degrees F)/ (BTU/h)
C- (hr. square foot degrees F)/ (BTU)
D- (BTU)/(hr. square foot degrees F)
A cooling system with a sewer vent concluding at 18 inches above the intake shall have MINIMUM horizontal distance between the sewer vent and fresh air intake of __ feet.
A- No minimum distance is required
B- 10 feet
C- 5 feet
D- 2 feet [Show Less]