What are the common faults and solutions of vacuum tube furnace？

Vacuum tube furnaces may encounter various faults during use. Here are some common faults and their solutions:
1. Abnormal temperature
①. High temperature alarm or display temperature not reaching the set value
Check the parameters of the thermostat: First, check whether the parameters of the thermostat in the work area are normal, and refer to other thermostats in normal use to calibrate all parameters.
Check the solid-state relay: After a power outage, use a multimeter to measure the resistance between the two output points of the solid-state relay. Normally, the resistance should be several megohms or more. If it is broken down, there is almost no resistance and a new one of the same model should be used.
Check the thermocouple probe: With power on, gently shake the thermocouple probe in the corresponding working area by hand and observe whether the temperature controller displays a large jumping amplitude. If this phenomenon occurs, it indicates poor contact of the thermocouple probe and needs to be replaced with a new one.
Check the heating tube: If there are no problems with the thermostat and thermocouple, it is necessary to test whether the heating tube is working properly when powered on. After powering on and starting up, start heating. According to the circuit diagram, directly use a test pen to test the wires connected to the heating tube in the corresponding working area (the white high-temperature wire on the solid-state output terminal is the one) to see if there is electricity arriving. If there is electricity arriving, it is necessary to use a clamp meter to measure whether the current is different from other working areas. Under normal circumstances, the difference is not significant.
2. Mechanical structural failure
①. The door is not tightly closed
Check if the hinges of the door are loose, if the buckle is deformed, if the sealing strip at the door is damaged, and if the door panel is deformed.
②. The fan has abnormal noise
Carefully check if any foreign objects have entered the impeller of the fan or if the screws securing the motor are loose.
③. Pneumatic valve cannot operate
Check whether the corresponding solenoid valve can work normally and whether the compressed air pressure meets the working requirements.
3. Electrical malfunction
①.After all switches are turned on, the indicator light does not light up
Replace fuse: It may be that the fuse is broken. Check for a short circuit and replace the fuse.
②. The ammeter has no current, but the voltmeter has electricity
Replace heating element: It may be that the heating element is damaged. Open the door to observe which heating element is broken, and then replace it. Do not replace all of them.
③. The voltage and power supply are normal, but the vacuum tube furnace is not working
Reset parameters: It may be due to an error in the parameters of the electric furnace. Contact the manufacturer or professional personnel to reset the parameters.
4. Vacuum problem
①. Insufficient vacuum degree
Check the air source: Confirm whether the vacuum air source is normal (such as -95KPa or above), and whether the compressed air pressure is normal (the normal range of use is 0.4-0.6MPa).
Check the vacuum gauge: Check if the vacuum gauge is in good condition and compare it with a vacuum gauge in normal use to see if the parameters are normal.
Check sealing: Check if the door is tightly closed, if the sealing film at the door is damaged or deformed, and if there are any foreign objects on the door panel. If there is no problem with the door, it is necessary to check the pipes, pneumatic valves, thermocouple entry points, and other positions in the corresponding work area, and re apply AB glue for sealing.
5. Other faults
①. The temperature displayed on the instrument does not match the temperature in the layout area
Adjusting temperature measurement points or calibration: It is normal for the temperature measurement points to deviate from the layout points or for the resistance values of the heating elements to deviate at the microscopic level. You can adjust the layout position or notify maintenance personnel to manually correct it.
In summary, the faults of vacuum tube furnaces may involve multiple aspects such as temperature, mechanical structure, electrical, vacuum, etc. The solutions also need to be determined according to specific situations. In the process of operation, if encountering problems that cannot be solved, the manufacturer or professional maintenance personnel should be contacted in a timely manner for handling.