Upon arrival client stated they had another company out and diagnosed a bad heat kit on 2 year old Lennox heat pump. Inspected system to find no signs of heat kit bad. Asked client what prompted them to the service call originally and they stated that they had a weird smell coming from vents. Previous company stated the smell was from the burnt heat kit and all the (biological growth) I found today was burn marks. Advised client heat kit was good and also tested while on site. Did highly recommend cleaning of the air handler cavity, pulling and chemically cleaning the blower wheel assembly, and installing a in duct air purification system with a germicidal lamp with a maintenance membership. Client signed estimate and wants work performed on the 13th of this month.