The constant temperature and humidity test chamber consists of two parts: temperature control (heating, cooling) and humidification. By installing a rotating fan at the top of the box, air is discharged into the box to achieve gas circulation and balance the temperature and humidity inside the box. The data collected by the temperature and humidity sensors built into the box is transmitted to the temperature and humidity controller (micro information processor) for editing and processing, and temperature and humidity control instructions are issued. This is achieved through the joint operation of the air heating unit, condenser tube, and water tank heating and evaporation unit.

Do you know how to solve the following problems that may occur if the constant temperature and humidity test chamber is used for a long time without proper maintenance?

1、 The temperature and humidity display in the constant temperature and humidity chamber is abnormal

1. The temperature and humidity controller of the constant temperature and humidity box displays an abnormal temperature. At this point, we first need to check the over humidity protector in the control room to see if it is still at the 150 ℃ position.

2. Next, check if the pipelines in the laboratory have not been cleaned for too long, causing poor water flow. Then, check if there is water in the upper water tank. If there is no water, check if there is water in the lower water tank.

3. Finally, check if there is a short circuit in the solid-state relay for humidity. If there is no problem with the heater, we can use the AC voltage range of the electric meter for detection.

4. You can also turn off the main power of the constant temperature and humidity chamber, open the drain valve under the heating bucket to a position parallel to the pipeline, drain the water inside, clean the dirt inside, then remove the silicone pipeline, scrub it in water, and after maintenance, reinstall it in the opposite direction according to the removal method. After the installation is completed, it is necessary to close the drainage valve under the humidification bucket to a position perpendicular to the pipeline, and then turn on the main power supply behind the machine.

2、 Frequent "machine jumping" phenomenon occurs during daytime work, and the cooling effect is normal at night

Analysis: If the cooling effect is normal at night, it indicates that the cooling system and circuit system are working properly. This suggests that it is caused by external factors in the constant temperature and humidity test box, such as poor heat dissipation from the condenser.

Inspection: The reasons for poor heat dissipation in the condenser are:

(1) The condenser indicates that it is too dirty

(2) There is air in the refrigeration system

(3) The surrounding air does not flow

(4) The ambient temperature is too high

(5) Oil film forms on the inner surface of the condenser.

Processing result: The cooling effect of the test chamber at night is normal, which eliminates the reasons (1), (2), (3), and (5) mentioned above. Moving the test chamber elsewhere will no longer cause the machine to jump. It is determined that the poor heat dissipation of the condenser is caused by the constant temperature and humidity test chamber being close to the heat source.

Solution: Move the constant temperature and humidity test chamber to a well ventilated location away from heat sources to troubleshoot the issue.

3、 How to solve overpressure

Firstly, we should confirm the ambient temperature, as the vast majority of overpressure is caused by excessively high ambient temperatures. Confirm if the room temperature is too high due to summer or lack of ventilation. The suitable temperature for a constant temperature and humidity test chamber is generally between 5-28 ℃.

If the temperature in the room does not exceed the above mentioned level, should the equipment be placed too close to the wall or corner when placing the constant temperature and humidity test chamber, as this will result in poor heat dissipation and trigger an alarm.

Another consideration is whether the test chamber has been cleaned since it was purchased? Generally, large refrigeration components such as condensing fans and condensers can be seen below the machine, i.e. in the refrigeration system, and whether the condensing fans and condensers are already covered in dust. If so, please clean it up in a timely manner, as this small and inconspicuous dust is preventing it from dissipating heat. It is recommended to clean once a month or every quarter, and a vacuum cleaner or other auxiliary tools can be used during cleaning. It is important to ensure that cleaning is done while the machine is stopped.

4、 The damp heat system has malfunctioned

Possible manifestations include: the constant temperature and humidity chamber displaying 100% humidity, inability to lower the humidity at low humidity points, or water shortage in the water tank. What should I do in these situations?

The specific solutions for slow or no increase in humidity are as follows:

1. Check if the humidity OUT on the controller has an output, or if it has a 100% output

2. Check if the SSR2 signal light is on. If it is on, you can use a clamp gauge to measure the current. If there is no current, it may be due to the following reasons:

a. FQ2 circuit breaker tripped, cutting off the heating circuit;

b. The humidifier solid-state relay SSR is damaged, with signal input but unable to conduct;

c. Humidifier tube damaged;