Customer stated when heat running system will shake floor and make very loud noise. Thoroughly inspected ICP package. Heat pump. Checked blower wheel. Cleanliness tighten fan blade on condenser fan motor. Check ductwork under house. Cannot hear noise at this time. Customer stated unit makes noise at night while running in heat cycle system through defrost customer stated that is not the sound. They are hearing. I asked customer if she could record sound next time unit makes noise. Cannot find problem with system at this time. Ask customer to call back if system acts up again