Refrigeration Dryer Failure and Repair Methods

1.There is no display on the panel of the refrigeration dryer, and the indicator light is off

Check whether the power supply is normal and whether there is voltage input. Check and repair if there is any disconnection at the wire connection. Check whether the control circuit board has voltage input. If the indicator light on the control panel is still off, it proves that the circuit board is faulty and needs to be replaced. If there is no voltage input, check the external power supply terminal

2.Power on, the power indicator light is on, but the machine cannot run after pressing start?

After pressing start, check whether the running indicator light on the panel is on. If the running light is on, it proves that the control system is not malfunctioning. It is necessary to check the compressor terminal and whether there is voltage input.
If there is voltage but the compressor cannot run, then the compressor is faulty. (Note: There is a thermal protector in the junction box of a small compressor. The thermal protector should be turned on for normal operation. Therefore, before measuring the compressor voltage, check whether the thermal protector is normal.) If there is no voltage input, it is required Check the capacitors and contactors in the wire box inside the machine.

3.If there is less refrigerant infusion, what happens to the cold drying opportunity?

Evaporating pressure and condensing pressure are lower than normal operation, but the air dew point cannot drop.
Compressor shell is hot

4.If there is too much refrigerant infusion, what happens to the cold drying opportunity?

Because the refrigerant liquid is stored in the condenser, the condensing area is reduced, which causes the pressure of the refrigerant to rise, and in severe cases, it causes a high-pressure trip.
The load of the refrigeration compressor increases and it is difficult to start
The refrigerant is not fully vaporized in the evaporator, so that the wet vapor enters the compressor, and there is a danger of "liquid compression"
As the condensing pressure increases, the cooling capacity of the compressor decreases and the air dew point increases In order to protect the normal operation of the compressor, the refrigeration dryer is set up: refrigerant high pressure protection and refrigerant low pressure protection. The low-pressure protection of refrigerant is 0.2MPa, the high-pressure protection value of refrigerant is 2.6MPa for air-cooled, and 2.3MPa for water-cooled.

5.Refrigerant high pressure protection

A:Air-cooled refrigerated dryer
The high-pressure protection of air-cooled refrigerant is generally due to dirty or fouling of the condenser radiating fins, and a dry air source is required to purge the condenser
Chronic leakage of the evaporator; a chronic leakage of the evaporator at the beginning will cause insufficient cooling capacity, the machine has no cooling effect, and the high pressure of the refrigerant will protect
Clogged refrigeration components, such as filter driers and thermal expansion valves
External reasons; high intake air temperature, too much flow, fast air flow, heavy load, high ambient temperature, insufficient heat dissipation conditions will all cause high pressure protection

5.Refrigerant high pressure protection

A:Air-cooled refrigerated dryer
The high-pressure protection of air-cooled refrigerant is generally due to dirty or fouling of the condenser radiating fins, and a dry air source is required to purge the condenser
Chronic leakage of the evaporator; a chronic leakage of the evaporator at the beginning will cause insufficient cooling capacity, the machine has no cooling effect, and the high pressure of the refrigerant will protect
Clogged refrigeration components, such as filter driers and thermal expansion valves
External reasons; high intake air temperature, too much flow, fast air flow, heavy load, high ambient temperature, insufficient heat dissipation conditions will all cause high pressure protection

B:water-cooled refrigerated dryer
For water-cooled refrigerated dryers, first check whether the cooling water flow is too small, the water temperature is too high, and the water pressure is too low;
Condenser sewage fouling;
Large intake load, large flow, high temperature, fast flow rate;
Internal leakage of evaporator;
The cooling element is clogged.

6.Refrigerant low pressure protection

Refrigerant low pressure protection is usually caused by the leakage of refrigerant from the outside of the refrigeration system. In the shutdown state, the pressure displayed by the refrigerant high and low pressure gauge (the outermost scale of the dial) is below 0.2MPa, then it is obviously an external leakage If leak detection is required, add refrigerant again
Pressure switch failure;
Refrigeration element blocked
The ambient temperature is too low and the load is too small;
The fan of the air-cooled model keeps running, and the cooling water flow of the water-cooled model is too large

7.High pressure of refrigerant is low, low pressure of refrigerant is high

The high pressure of the refrigerant corresponds to the low pressure of the refrigerant, and the low pressure of the refrigerant changes with the change of the high pressure. Therefore, the high pressure of the refrigerant is high or low, and the low pressure of the refrigerant will also be high and low
The operating pressure of the air-cooled fan is adjusted to a low level before it is adjusted to the working pressure of 1.6MPa, and it has been working;
Water-cooled type Cooling water flow is too large
The load of the refrigeration dryer is small
The ambient temperature is too low;
Chronic leakage of refrigeration system