When the freeze dryer is running, refrigeration is very important, which directly determines the operating efficiency of the equipment, but there are many reasons why the equipment does not cool, so what are the reasons for this?
1. ① The expansion valve is opened too much, at this time, the temperature of the shelf or the water vapor condenser does not drop to the set value, and the compressor is seriously frosted.
②The opening of the expansion valve is too small, and the temperature cannot be lowered at this time, but the temperature of the compressor is very high, and there is no frost on the suction valve. The temperature of the device is much lower.
2. The refrigeration system is not blocked smoothly, check whether the condenser is blocked by foreign objects, which will cause poor heat removal effect.
For example, the filter is blocked, the valve is not opened, the solenoid valve is out of order, the expansion valve is blocked, etc.
3. The refrigerant is insufficiently charged, the temperature cannot be lowered at this time, and the suction pressure is low, and there is no frost at the suction valve.
4. The paper pad on the upper part of the compressor valve plate or the lower part of the cylinder is broken down or ruptured, or the compressor suction and exhaust valve plates are broken.
Remedy: (1) Adjust the expansion valve.
(2) Unblock the refrigeration system and replace the parts.
(3) Charge the refrigerant.
(4) Replace the paper pad or valve plate.
5. Whether the ambient temperature is too high, and whether the air inlet and outlet of the freeze dryer are blocked, the air inlet and outlet of the freeze dryer can be larger than 10CM without obstructions, and the nearby ambient temperature cannot be higher than 30 degrees to prevent the compressor from overheating and burning out.