10JAN2022 Jason B Arrived for previous customer no heat. Spoke with homeowners about the systems performance. It will work when it’s warm, but when it’s cold It won’t heat. Cycled system at thermostat inspected filters, HSI, heat exchanger, pressure switch, inducer, amps, and all components. Found system being filtered twice, causing an excessive heat rise. Found flame sensor very dirty, and intermittently not detecting flame. Found refrigerant oil all over the top of the furnace as well. Spoke with homeowners about my findings. Cleaned flame sensor and removed extra filter. Went over leak searches. They are just limping the system along for now and will address the leak when they have to. System is operating normally at this time. 1 yr labor warranty.