Mechanical, Electrical, and Plumbing Systems Flashcards
6 cards from real General Contractor License practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Mechanical, Electrical, and Plumbing Systems flashcards as text
Under ASHRAE 62.2, which ventilation method is considered the minimum standard for indoor air quality in new residential construction?
Answer: Whole-house mechanical ventilation
ASHRAE 62.2 requires whole-house mechanical ventilation in new residential construction to maintain acceptable indoor air quality continuously.
A GFCI outlet must be installed in which of the following locations in a residential bathroom?
Answer: All outlets regardless of location
NEC requires GFCI protection for ALL receptacle outlets in bathrooms, regardless of their distance from water sources.
What is the purpose of an air admittance valve (AAV) in a plumbing drain-waste-vent system?
Answer: Allow air into drain lines without extending vent pipes through the roof
An AAV allows air to enter the drain system to equalize pressure and prevent siphoning of trap seals without requiring a full vent pipe penetration through the roof.
According to the IRC, what is the maximum distance a P-trap can be located from its fixture drain outlet (trap arm length)?
Answer: 24 inches
The IRC limits trap arm length (distance from the trap weir to the vent) to 24 inches for a 1.5-inch diameter drain to ensure adequate drainage and trap protection.
Which electrical conductor color is designated as the grounding conductor per NEC in the United States?
Answer: Green or bare copper
NEC designates green insulation or bare copper wire as the equipment grounding conductor in branch circuit wiring.
When installing forced-air HVAC ductwork, what is the primary reason supply registers and return air grilles should NOT be located in the same wall cavity?
Answer: Short-cycling occurs when conditioned air is immediately pulled back to the return
Placing supply and return air in the same cavity causes short-cycling, where conditioned air is pulled back to the return before reaching the occupied space, reducing system efficiency.