Refrigeration & Air Conditioning Mechanic Red Seal · Question
During a routine service, a gas furnace's main burner flame appears mostly yellow with flickering tips and distinct soot formation on the heat exchanger. What is the most probable cause of this condition?
A yellow, sooty flame with flickering tips is a classic indication of incomplete combustion due to insufficient primary or secondary combustion air, leading to
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Question: During a routine service, a gas furnace's main burner flame appears mostly yellow with flickering tips and distinct soot formation on the heat exchanger. What is the most probable cause of this condition?
Answer options: ✅ Insufficient combustion air entering the burner assembly.
- Excessively high manifold gas pressure.
- A clogged or restricted vent connector.
- A faulty igniter not providing sufficient ignition energy.
Correct answer: Insufficient combustion air entering the burner assembly.
Explanation: A yellow, sooty flame with flickering tips is a classic indication of incomplete combustion due to insufficient primary or secondary combustion air, leading to carbon monoxide production and inefficiency.
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- Which of the following refrigerants is a hydrofluorocarbon (HFC) and has a high ozone depletion potential (ODP
- Which component is responsible for compressing the refrigerant vapour to a high pressure and temperature?
- According to the Canadian Electrical Code (CEC), what is the minimum required working clearance in front of el
- What is the main operating characteristic difference between a fixed orifice (capillary tube) and a Thermostat
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