G3 G3 - Gas Technician Level 3 Appliance Installation and Service Questions and Answers 1 — Questions and Answers
Question 1: What is the minimum clearance from combustible materials typically required when installing a gas-fired forced-air furnace in the US?
- 1 inch on all sides
- Follow manufacturer's listed clearances (Correct answer)
- 6 inches on all sides
- 12 inches on the front only
Correct answer: Follow manufacturer's listed clearances
Appliance clearances must follow the manufacturer's listed installation instructions, which are based on testing and listing by a recognized authority.
Question 2: Before lighting a gas appliance pilot, a technician should first:
- Turn the gas valve to the pilot position immediately
- Check that the area is free of gas odor and purge any accumulated gas (Correct answer)
- Ignite the burner directly with a match
- Close all supply valves fully
Correct answer: Check that the area is free of gas odor and purge any accumulated gas
Purging accumulated gas and confirming no gas odor prevents ignition of a potentially explosive mixture.
Question 3: When installing a gas dryer, the flexible connector between the dryer and the house piping must be:
- As long as possible to allow movement
- Approved for gas use and not concealed inside walls (Correct answer)
- Made of rubber tubing
- Connected using compression fittings only
Correct answer: Approved for gas use and not concealed inside walls
Gas connectors for appliances must be listed for gas service and must remain accessible, not run inside walls or floors.
Question 4: Which type of valve must be installed within 6 feet of a gas appliance and be accessible for shutoff?
- Pressure regulator
- Manual shutoff valve (Correct answer)
- Check valve
- Solenoid valve
Correct answer: Manual shutoff valve
A manual shutoff valve must be located within 6 feet of each appliance and remain readily accessible to quickly cut off gas supply in an emergency.
Question 5: When connecting a gas range in the US, the appliance connector should be:
- Hard-piped with black iron only
- A listed flexible metal connector no longer than 6 feet (Correct answer)
- Any plastic tubing rated for gas
- A rubber hose with clamp fittings
Correct answer: A listed flexible metal connector no longer than 6 feet
ANSI Z21.69/CSA 6.16 requires listed flexible connectors for gas ranges, limited to 6 feet in length.
Question 6: A gas appliance that is 'listed' means it has been:
- Registered with the local utility company
- Evaluated and certified by a nationally recognized testing laboratory (Correct answer)
- Inspected by the installing technician
- Approved verbally by the local authority having jurisdiction
Correct answer: Evaluated and certified by a nationally recognized testing laboratory
A listed appliance has been evaluated against applicable safety standards by an NRTL such as UL or CSA.
G3 G3 - Gas Technician Level 3 Appliance Installation and Service Questions and Answers 1
What is the minimum clearance from combustible materials typically required when installing a gas-fired forced-air furnace in the US?