Problem Explanation：
1. Abnormal sound produced in the process of movement is mainly caused by the fact that the heater has a dumping protection and a tipping switch inside. When the equipment is transported or moved, the iron ball inside the tipping switch will meet the plastic shell of the internal tipping switch, which will lead to abnormal sound of the machine.
2. When the heater is switched on and used, the internal temperature will rise sharply, which will cause the body to be heated and cause a heating effect, causing some contact parts to slip and make noises. When the body temperature is constant, the sound will disappear, which is a normal phenomenon.