I installed a new heat pump but I smell a weird odor

My husband and I have been living in our forty year old house for about ten years now.

When we first moved in we knew that we had a big commitment.

We knew that we would have to do a lot of updating, repairs, and replacing of appliances and flooring. After three years of living in the house we finally had everything that we wanted to be done. It was such a relief but we also knew that eventually there would be other replacements that we would have to do. One of the replacements that had to be done was our heat pump. We figured that it needed replacing when it completely broke down on us. Our HVAC technician told us that since the heat pump was over twelve years old he considered that we replace it. After a week of having a new heat pump and it being on, we could smell a weird odor. For the second time in one week, we called our HVAC technician. He inspected the new heat pump, looked at the vents and ductwork to make sure that they were clean. In fact, everything was clean since we had ductwork cleaning a month ago. Our HVAC technician told us that he believed it was from residue burn off of the inside of the air handler. It was a big relief to hear this, he also told us to keep an eye on it and if we still smell it in the next few weeks to give him another call.
heater