HVAC Code Compliance 4

Question 1

Under the National Electrical Code (NEC) Article 440, what is the purpose of the branch-circuit short-circuit and ground-fault protective device for a hermetic refrigerant motor-compressor?

Accepted Answer

Protects the branch circuit conductors and equipment from short-circuit and ground-fault conditions

Answer

NEC 440 requires a branch-circuit protective device sized to protect conductors and equipment from short-circuit and ground-fault currents, separate from overload protection.

Question 2

Per the International Mechanical Code, when must a carbon monoxide alarm be installed in a dwelling that has a fuel-burning appliance?

Accepted Answer

Outside each sleeping area in the immediate vicinity of bedrooms

Answer

The IMC and IRC require CO alarms to be installed outside each sleeping area in the immediate vicinity of bedrooms in dwellings with fuel-burning appliances.

Question 3

Which ASHRAE standard specifically addresses the safety of refrigeration systems and specifies refrigerant classifications like A1, A2L, and B2?

Accepted Answer

ASHRAE 34

Answer

ASHRAE Standard 34 establishes a refrigerant designation system and safety classification, grouping refrigerants by toxicity (A/B) and flammability (1/2L/2/3).

Question 4

Per the International Fuel Gas Code, what is the maximum pressure drop allowed in a low-pressure natural gas piping system from the meter to the appliance?

Accepted Answer

0.5 inch W.C.

Answer

The IFGC allows a maximum pressure drop of 0.5 inch water column in low-pressure gas piping systems to ensure adequate pressure at appliances.

Question 5

Under the International Mechanical Code, what ventilation requirement applies to a commercial kitchen exhaust hood?

Accepted Answer

Makeup air must be provided at 80-100% of exhaust volume

Answer

The IMC requires that makeup air be provided at approximately 80 to 100 percent of the exhaust volume to maintain proper pressure balance in commercial kitchens.

HVAC Practice Test

HVAC Practice Test

HVAC Code Compliance 4