Gas Piping Systems Flashcards
7 cards from real Master Plumber Exam practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Gas Piping Systems flashcards as text
A gas-fired water heater installed in a garage must be elevated so the ignition source is at least how high above the floor?
Answer: 18 inches
Appliances with open flames or ignition sources in garages must be elevated at least 18 inches above the floor to keep ignition above the level where heavier combustible vapors accumulate.
When two or more gas appliances are served by a common vent, the vent must be sized based on:
Answer: The combined total BTU input of all connected appliances
Common vents must be sized for the total combined BTU input of all appliances connected to ensure adequate draft and safe flue gas removal.
What is the purpose of an excess flow valve (EFV) on a gas service line?
Answer: To automatically shut off gas flow if the pipe is severed or flow exceeds a set threshold
An excess flow valve automatically closes when gas flow exceeds a preset rate, such as when a service pipe is accidentally broken.
Under IFGC, flexible gas connectors are prohibited from passing through:
Answer: Floors or walls
Flexible gas connectors must not be concealed within or pass through floors, walls, ceilings, or partitions.
A plumber discovers an existing uncoated steel gas pipe buried in soil. The correct action is to:
Answer: Replace or coat it with approved corrosion protection
Underground steel gas piping must be protected from corrosion with approved coatings or cathodic protection; uncoated pipe must be corrected.
What is the maximum length of an outdoor LP gas appliance connector (flexible connector)?
Answer: 6 feet
Outdoor LP appliance connectors, like those for gas grills, are also limited to a maximum of 6 feet in length.
A plumber is installing a gas line and must cross an electrical panel location. The gas pipe must maintain a minimum clearance of how many inches from the panel?
Answer: 6 inches
Gas piping must maintain a minimum of 6 inches clearance from electrical panels and equipment to reduce arc and ignition risk.