I am a highly skilled and experienced home service professional. I recently completed a job in a residential home where I was called to inspect and repair a gas furnace. Upon arrival, I found that the furnace was not producing heat and was emitting carbon monoxide. I performed a combustion test to determine the cause of the issue and found that the furnace was operating within the safe operating range. I then repaired the issue and tested the furnace again, and the carbon monoxide levels were within the safe range. The customer was very pleased with the work I performed and expressed gratitude for my expertise and professionalism.