CFESA Gas Equipment and Safety 3 — Questions and Answers
Question 1: What is the correct procedure for converting a commercial range from natural gas to LP gas?
- Adjust regulator pressure only
- Replace orifices with LP-rated orifices and adjust regulator to LP pressure (Correct answer)
- Increase primary air only
- Replace the gas valve and regulator only
Correct answer: Replace orifices with LP-rated orifices and adjust regulator to LP pressure
Converting from natural gas to LP requires replacing burner orifices with smaller LP-rated ones and setting the regulator to the correct LP manifold pressure.
Question 2: According to NFPA 96, what is the required clearance between commercial cooking equipment and combustible surfaces?
- 3 inches
- 6 inches
- 12 inches
- Clearances are set by equipment manufacturer specifications (Correct answer)
Correct answer: Clearances are set by equipment manufacturer specifications
NFPA 96 requires that clearances between commercial cooking equipment and combustible surfaces follow the equipment manufacturer's listed specifications.
Question 3: What is the function of a standing pilot system versus an electronic ignition system in commercial gas equipment?
- Standing pilot burns continuously; electronic ignition lights only when the appliance calls for heat (Correct answer)
- Electronic ignition uses a thermocouple; standing pilot uses a spark
- Standing pilot is more energy efficient than electronic ignition
- Electronic ignition requires a pilot light to operate
Correct answer: Standing pilot burns continuously; electronic ignition lights only when the appliance calls for heat
A standing pilot burns continuously to be ready for immediate ignition, while electronic ignition generates a spark or hot surface only when the burner is called to fire.
Question 4: When servicing a commercial broiler, technicians should check the infrared burner for:
- Carbon monoxide output only
- Cracks, plugged ports, and uneven heat distribution (Correct answer)
- Manifold pressure only
- Pilot orifice size only
Correct answer: Cracks, plugged ports, and uneven heat distribution
Infrared burners must be inspected for cracks in the ceramic tile, clogged ports, and uneven glowing patterns that indicate improper combustion.
Question 5: Which tool is used to measure gas manifold pressure in commercial cooking equipment?
- Clamp meter
- Manometer or magnehelic gauge (Correct answer)
- Multimeter
- Anemometer
Correct answer: Manometer or magnehelic gauge
A manometer or magnehelic gauge measures gas pressure in inches of water column (W.C.), the standard unit for manifold pressure measurement.
Question 6: A commercial gas griddle produces uneven heating across the cooking surface. The most likely cause is:
- Low supply voltage
- Clogged or misaligned burner tubes or orifices (Correct answer)
- Faulty thermocouple
- Low refrigerant charge
Correct answer: Clogged or misaligned burner tubes or orifices
Clogged burner tubes or misaligned orifices restrict gas flow to sections of the griddle, causing uneven heat distribution across the cooking surface.
CFESA Gas Equipment and Safety 3
What is the correct procedure for converting a commercial range from natural gas to LP gas?