Technical

Five common troubleshooting methods for cryogenic baths

1. When the cryostat is running for the first time, the instrument does not heat up or cool down. What's wrong?

The low-temperature thermostatic bath generally uses a compressor that integrates heating and cooling, which can avoid multiple operations of the instrument program and prolong the heating and cooling time. The instrument is generally equipped with heating insurance and cooling insurance. Generally, the instrument does not heat or cool , you can first check whether the heating insurance or refrigeration insurance of the instrument is loose. If not, you can unscrew the condom to check whether the fuse is burned out. If the fuse is replaced in time, the instrument can run normally.

2. The low temperature thermostat has been used for more than a year, and the cooling speed is getting slower and slower?

Answer: It seems that many faults and failures of the low temperature thermostat are caused by the lack of regular maintenance. The electric power of the water circulation of the low temperature constant temperature tank and the heat taken by the refrigerant from the load need to be discharged from the radiator at the front ventilation hood. If the front ventilation hood is full of dust and willow cotton, it will hinder the dissipation of this heat. The cooling effect will be greatly reduced. Generally speaking, the decrease in cooling capacity under normal use conditions is caused by poor ventilation and heat dissipation or too high ambient temperature. There is also the timely maintenance of the inside of the tank, if it is not used for a long time, it should be cleaned in time and kept dry.

3. The water cycle was used normally before, but now it is found that the noise is much louder than before?

Answer: This problem is also related to the water circulation of the low temperature constant temperature tank. We all know that there are very few impurities in the water, even if distilled water is added to the water tank, it is impossible to completely guarantee that there are no impurities at all. For water circulation, the temperature is generally set at 20°C, which is especially suitable for the growth and reproduction of microorganisms. After a long time, these microorganisms will block the filter of the waterway, causing the backwater to be blocked, and the pump will make a lot of noise. Sometimes these microorganisms attach to the surface of the heat exchanger, causing the heat transfer effect of the heat exchanger to deteriorate and the cooling capacity to decrease. Therefore, do daily maintenance work, clean the inner tank regularly, stop using it for a long time, and keep the tank dry. For daily cleaning and precautions, please refer to the precautions for the low temperature thermostat.

4. There is air leakage in the external circulation of the low temperature constant temperature tank. Sometimes there are a few drops on the ground in a while. Is there a leak in the waterway?

Generally speaking, all the interfaces are sealed with high-strength glue during the transfer process of the instrument, and there will be no leakage in the waterway. However, sometimes when the ambient temperature is relatively high and the relative humidity in the air is too high, due to the low temperature operation, dew is easy to condense on the water pump, water pipe joints and external water pipes in the water circuit of the water circulation, and it will drip on the ground after accumulation. , It is not a water leak, you can use it with confidence. If you feel uncomfortable doing this, you can turn on the air conditioner to lower the indoor temperature.