Tech Cody arrived to customer's home and met the homeowner. Customer informed me that when she turned her system on to heat this morning they smelled something burning. I turned the system to heat and smelled to burning smell. I went to the indoor equipment, the unit is a trane air handler, the unit was operating normally. I checked the outdoor heat pump, the compressor and fan motor were operating within manufacturer range and the auxiliary motor starter was within tolerance. The customer told me that this morning was the first time that the unit was put into heat mode this season. The burning smell was the dust on the heat strips burning off from first use this season. I informed the customer of my findings and the system was running normally when I left.