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Guchen Thermo Truck Refrigeration Units FAQ (1)

Jun  06,2017

truck refrigeration units FAQ is from our experienced sales staff, who make these conclusions of FAQs for truck reefer units users based on our clients’ frequent questions.
In order to help your truck reefer units working better, please look through these FAQ, and hope it do help you.

Question 1: Truck refrigeration units’ low pressure reading is nearly to zero, high pressure is lower too, after a few minutes, high and low pressure keep still. Why is it and how can I deal with this truck reefer units problem? 

Answer: It is possible that expansion valve blocked or temperature wrap break up (you can see it obviously), so the expansion valve cannot open.
Reservoir or filter is blocked; or feed liquid valve cannot open, which results in the big temperature difference between these spare parts.
If your reefer unit has liquid solenoid valve, please check out whether the valve powers on. Or the valve is broken, you cannot charge.
In order to solve these problems, it’s better to change the expansion valve or clean it. Guchen Thermo supplies expansion valve from Danfoss with a better performance, and not easy to blocked by filth or ice.

Question 2: It displays HPER (High Pressure Error), why is it?

Answer: As for the R134a refrigerant truck reefer units, the HPER is because: if the refrigerant is not enough or no refrigerant, it will shows error code once you start off the units. So as for this condition, you should refill enough refrigerant. The Guchen Thermo truck refrigeration units have fewer refrigerants, which can save your cost.
Condenser fans not working and pressure higher can also result in the units’ alarm once you start off it for minutes. So in this time, you should examine whether the condenser fans damage. If it damage, change a new one. What’s more, if there is something wrong in pressure switch circuit, once you start off, it also reads error code.

Question 3:  How can I protect my truck refrigeration units’ compressors?

Answer: In order to protect your truck reefer units’ compressors, we give the following advices:
A)As for the Unicla compressors, you should add RL32H refrigerant oil for reefer units, the refrigerant oil amount should be 10-15% of the reefer units’ coolant. A part of refrigerant oil adds into compressor, and the rest of part adds into oil content. Before you fill in refrigerant, you should screw compressor clutch drive plate for about ten circles in order to push the refrigerant oil into high-pressure hose, which can protect too much oil in compressor from slugging liquid, and protect the compressor.
B)If fluorine leaks or fluorine decreases, you should refill the same model refrigerant oil for compressor using.
C)It’s better to start off units under the engine idle in order to reduce the shock to compressor, prolong the compressor service life.

Question 4: How can I judge whether the refrigerant is enough or not and when I fill refrigerant for the first time?

Answer: we don’t recommend you to judge whether refrigerant is enough based on the pressure, because weather and ambient temperature is so changeable, so pressure changed quickly, which can give you a wrong signal.
Observation method works well: when you fill refrigerant, observe the sight glass. At first, bubbles from more to less, when few seconds for producing one bubble; the refrigerant amount is exactly enough! If there are no bubbles producing, it means you fill too much refrigerants!

Question 5: Why my reefer truck body’s temperature cannot decrease down?

Answer: when your reefer truck body temperature cannot decrease, check whether the high pressure low and low pressure high. If it is, the following factors can result in this situation:
A)Deforesting solenoid valve leakage.
B)Expansion valve air flow is too much, low pressure tube and compressor are frosting.
C)Compressor high-low pressure leakage.

To be continued...

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:

TR series Truck Freezer Units
C series Truck Chiller Units
TS series Independent Truck Refrigeration Units
Electric Van Refrigeration Units
TR series Van Freezer Units
C series Van Chiller Units
Transport Refrigeration Units Compressors
Transport Refrigeration Units Fans
Transport Refrigeration Units Electric Controller System

About Guchen Thermo After Sales Service:

◆ 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.


Please feel free to submit your inquiry information to us. We will contact with you as soon as possible.

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