How to solve the low pressure alarm of the chiller?

2021-09-09

1. Investigation factor 1: refrigerant leakage
There are leakages in the connecting pipes of the cooling system, such as solder joint leakage, corrosion leakage, fracture caused by mechanical vibration, human factors, etc., which will cause low pressure failure.
solution
First, use a leak detector (soap water, or a detergent mixed with water) or a halogen leak detector to find the leak. The leak is found, repair it and the welding equipment, and then keep the pressure at the test leak and vacuum (remember to vacuum, remove clean and then fill the refrigerant), according to the manufacturer's instructions before charging the refrigerant, the cooler can be Resume normal operation.
2. Troubleshooting factor 2: The cooling system is blocked
A. Impurity blockage
If the filter is clogged by dirt, it will only cause a slight decrease in cooling capacity, or even feel no effect. When the filter is slightly clogged, there will be a temperature difference between the inlet and outlet of the filter, which can be felt by holding the water inlet and outlet with your hand. When the blockage is severe, the filter will condense or frost. If there is condensation or frost (except for condensation after the chiller stops running under normal operating conditions), it can be judged that the filter is clogged.
solution
Replace the same model filter element
B. Ice block
The water in the system flows to the throttle valve (expansion valve) together with the refrigerant. After the throttle is expanded, the throttle outlet freezes, which blocks the throttle valve (expansion valve) and causes a low pressure failure.
solution
Replace the filter with the same model.
C. Damaged expansion valve
The expansion valve is affected by the environment during use. The presence of corrosive gases in certain environments can corrode the liquid, thereby corroding the expansion valve.
solution
Replace with a new expansion valve of the same model
3. Investigation factor 3: The heat exchange of the evaporator is seriously insufficient.
A. Insufficient water flow in the evaporator
The water pump is broken or foreign matter enters the water pump impeller, and the water inlet pipe of the water pump is leaking (difficult to check, careful analysis is required), resulting in insufficient water flow.
solution
Replace the water pump. Or disassemble the pump to remove the bad things in the impeller.
B. The evaporator is blocked by bad things
First of all, the problem of the water pump must be eliminated. When the equipment is normal, there will be no large amount of condensed water and frost on the surface of the compressor. When you see a large amount of condensed water and frost on the surface of the compressor, you can basically judge that the evaporator is blocked.
solution
If the evaporator is blocked or the evaporator tube is fouled, please disassemble the evaporator, take out the evaporator tube, and then rinse with a high-pressure water gun or soak and clean with a special chemical liquid.We produce 8HP Air-cooled Hot And Cold Integrated Machine.