How to detect potential problems with electric air heaters?

1. Stop the air heater and check the power supply to see if there's a wiring problem. Check whether all three phases are functioning properly or if there's a missing phase. If there's a missing phase, call an electrician immediately to repair it. Check to see if the fuses are intact and the unit is not damaged. Open the air heater's protective cover and use a multimeter to check if the individual heating elements are open.

2. Abnormal Temperature Gauge Display: If the temperature gauge on the air heater shows abnormal readings, first check to see if the air switch is closed and the control circuit is intact. If the heater doesn't reach a reasonable temperature after powering on, troubleshoot the cause. First, check to see if the fuse is intact. If there's no problem, then check to see if the heater itself is damaged. In winter, when temperatures often drop below 0°C, if no measures are taken, the water in the heater can easily freeze, affecting normal operation and potentially causing pipe ruptures. The causes of frozen surface coolers vary depending on the region. In milder regions, it may be because the preheating plate isn't installed in winter, leaving water inside the surface cooler. This water then draws in cold air and freezes.

During the winter, it's important to drain the water from the air cooler when not in use. For example, frozen and cracked air coolers in southern China during winter may be caused by extremely low temperatures on certain days, which prevents the return air from mixing properly with the fresh air, allowing the cold outside air to blow directly onto the air cooler. A mixing valve can be installed to thoroughly mix the fresh and return air. The air heater consists of multiple tubular heating elements, a housing, a protective cover, and a base. The heater is a tubular heating element made of high-temperature resistance alloy wire, protected by a stainless steel tube and filled with crystalline magnesium oxide. This element is formed through a compression process, resulting in excellent mechanical strength, high thermal efficiency, and wear and corrosion resistance. A flow guide baffle is installed within the housing to ensure uniform heating during air circulation. The control cabinet utilizes an intelligent digital temperature controller, high-power thyristors, and RTDs to form a measurement, regulation, and control circuit. The RTD converts the heater outlet temperature into a milliampere signal, which is then amplified and compared with the intelligent digital temperature controller for display. If the displayed value exceeds the set value, the thyristor turns off. When the displayed value falls below the set value, the intelligent digital temperature controller triggers the thyristor to conduct. When the displayed value approaches the set value (i.e., near the set value), the intelligent digital temperature controller changes according to the P, I, and D patterns, ensuring excellent control accuracy and regulation performance. Based on the milliampere signal sent by the RTD, the intelligent digital temperature controller automatically changes the number of trigger pulses for the thyristor. This controls the conduction angle of the thyristor per unit time, adjusts the voltage, and controls the heating power of the heating element, ensuring energy savings and a constant temperature, avoiding current surges, and extending the service life. If the equipment suddenly shuts down and restarts, the control cabinet can automatically and smoothly adjust.