Question 6: Why I cannot fill fluorine (refrigerant) to the truck refrigeration units cooling system?
Answer: if you connect the tube correctly, first fill the fluorine from high pressure, the refrigerant is not enough, and then start off the refrigeration units, you refill refrigerant from low pressure, but the low pressure and high pressure are very low, refrigerant cannot be refilled, it may be because of the expansion valve block.
The possible reason is that filth blocks expansion valve; so you can check the expansion valve, clean valve plug or change a new expansion valve.
If there is nothing wrong with expansion valve, it might be the problem of air and water left in vacuum system, so expansion is blocked by ice. To deal with this problem, just to re-pump air completely for a real vacuum condition again.
Question 7: What should I note for the first time usage of my small truck reefer units?
Answer: A)If it is a single cold-type unit (only in the condition of set temperature lower than ambient temperature, the unit can run), temperature range we give is just an approximate range of cooling temp; if heating is required, please consult our engineer.
B)Refrigerant charge amount is only for reference. For different configurations, the compressor, tube change, different season’s installation, compressor speed and so on can impact the amount of refrigerant. For the details, you can observe the sight glass, if there are two or three bubbles flowing, it means refrigerant is enough; if too many bubbles appears, it means refrigerant is not enough; if there is no bubbles, it means too much refrigerant is filled.
C)R404A unit vacuuming has a very strict requirement; otherwise it will affect the results of unit freezing. As for this, you need to use 4L / S vacuum pumps.
Question 8: How could I fill refrigerant R404A to my truck reefer units?
Answer: Charge refrigerant R404A method: Finish doing vacuum, set the pressure, starting to charge refrigerant from the high-pressure, sometimes you can fill enough refrigerant for one time; if the refrigerant is not enough, turn off the high-pressure valves, turn on the unit, and continue to charge from low pressure. In order to make sure the refrigerant liquid to the compressor before it has become a gas to prevent liquid strike, you can open the low pressure refrigerant valve a smaller point and fill refrigerant little by little, which also ensures the R404 refrigerant component. This point has a greater impact on cooling effect.
Question 9: Why the evaporator fans not working in my truck refrigeration units?
Answer: First, check out whether the refrigeration indicator light and evaporator fans indicator light is on or off; if both the lights are on, but evaporator fans are not working, check out whether the fans plug is charged with electricity.
If there is no electricity, check whether each evaporator fan relay pin is normal, and whether it is powered;
If the evaporator fan relay is normal, each point relay connections are normal, check whether the evaporator fan signal displays voltage;
If there is no voltages in the signal line, then check the back of controller, directly measure whether the evaporator fans controller output signal lines have voltage, if the controller displays evaporator fan lights are on, but no signal line voltage, it means the controller has internal fault.
The color of back controller line: evaporator fan line is purple; condenser fan line is gray.
Question 10: Why the high pressure and low pressure alarm and displays HPER and LPER (High pressure error and low pressure error)?
Answer: Currently as for the R404a truck refrigeration units, the voltage are divided into high and low pressure, so the reason for the alarm situation and composite pressure switches are difference:
A)When you turn on the unit, control panel show LPER low pressure alarm immediately
Reasons: ① The refrigerant is leak, pressure is lower than the low pressure switch, the alarm appears; ② low pressure switch circuit fault - breaker; ③ pressure switch itself fault - pressure switch cannot be closed; ④ control panel internal fault;
B)Start running for several minutes, low pressure alarm occurs LPER, Reasons: ① liquid supply magnetic valve is not open; ② expansion valve bulb capillary rupture led to the expansion valve cannot open; ③ system fouling;
C)Once you turn on the unit, immediately show HPER high pressure alarm.
Reasons: ① high pressure switch line fault - breaker; ② pressure switch itself fault - pressure switch cannot be closed; ③ controller internal fault;
D)Start running for several minutes, high-pressure alarm occurs HPER Reasons: ① condenser fan does not work; ② refrigerant charge is too much, the heat dissipation of condenser is not good.
About Guchen Thermo Company:
Guchen Thermo Co.,Ltd as the truck refrigeration units suppliers in China not only sell our units, but also we sincerely help our customers solve problems. All of our customers cooperate with us give a high praise of us on Guchen Thermo transport reefer units and sales persons’ service. We guarantee that the complete after sales service and professional technology help. Although Guchen Thermo is not famous as Carrier Transcold and Thermo King, we promise that the same quality with the famous brands!
Any one who has interest in the transport refrigeration units and want to start cold chain transportation business, please let us help!
About Guchen Thermo Products:
We have the following series transport refrigeration units for your cold chain transportation business:
◆ Guchen Thermo all the products had passed the quality system certification of ISO9001:2008. CE certification.
◆ 12 months or 60,000KM spare parts free change in the time of expiration date.
◆ 24 HOURS SERVICE for solving customers’ product problems.
◆ Guchen Thermo Distributors all over the world to serve customers timely.
About Guchen Thermo Distributors Locate in:
▲ South Africa