Because the magnesium oxide powder in the electric heating tube will absorb moisture, and the port of the heating tube is not completely sealed, in a relatively humid air environment for a long time, moisture will be in the electric heating tube . Under such a moment, the magnesium oxide powder, which functions as a heat conductor, is damp. Finally the electric heating tube will not generate heat.
1. Measure if there is any resistance value, if not, it is broken.
2. If there is still a resistance value, then check if there is any leakage phenomenon. Use a megohmmeter (insulation resistance meter) to measure the insulation resistance value. (The larger the insulation resistance value, the better the insulation.) If it is small, it means that the magnesium oxide powder in the electric heating pipe may be damp and weakens the insulation of the electric heating pipe.
(1) Put the electric heating tube in the oven and dry it to dehumidify the magnesium oxide powder.
(2) The electric heating tube is powered by low voltage for a while, and also can dehumidify.
The wiring problem is an important factor that causes the electric heating tube can not heat.
Therefore, the heating tube should not be stored for too long.