How to charge refrigerant for parking cooler VS02 PRO
Key points for parking air conditioner buyers and fleet operators
January 20, 2025
Below, Kevin from Vethy will briefly introduce how to charge refrigerant and the effectiveness of VS02 PRO.
So how should technicians or maintainers charge the refrigerant of the vethy VS02 PRO parking air conditioning system?
Before charging the construction machinery split parking air conditioning with R410A/R32 refrigerant, make sure that the system is fully installed and tested for air tightness. For systems without shut-off valves, it is necessary to evacuate the system to remove air and moisture. It is recommended to evacuate to an absolute pressure of less than 500 Pa and maintain it for at least 30 minutes to ensure that the system is dry.
After the vacuum is completed, turn off the vacuum pump and observe whether the system can maintain the vacuum state for a period of time (such as 15 minutes) to verify the air tightness of the system. If the vacuum is not maintained, the leak must be found and repaired.
Next, charge R410A/R32. In general, the charge amount is about 450 grams. Please refer to the technical manual provided by the manufacturer for specific values. Use a dedicated R410A charging device connected to the low-pressure end of the air conditioning system and slowly charge until the specified weight is reached. During the charging process, start the air conditioning system to ensure that the refrigerant is evenly distributed, and monitor the pressure gauge to ensure that the system is working properly.
Finally, check all connections again for leaks and complete the charging process after confirming that they are correct. Following the above steps can ensure the efficient operation and long service life of the construction machinery split parking air conditioner.
Vethy VS02 PRO Electric Parking AC: Fuel Savings and Environmental Benefits
Vethy VS02 PRO electric parking air conditioner is meticulously designed for trucks and heavy machinery, offering a revolutionary solution that operates on 12V/24V DC power from the vehicle’s battery. This innovative feature eliminates the need for engine idling, significantly enhancing usability while delivering remarkable fuel savings.
Consider a typical long-haul truck that travels 150,000 kilometers annually, with each stop involving three hours of rest. Traditional systems require the engine to idle, consuming approximately 2 liters of diesel per hour. By opting for the Vethy VS02 PRO, drivers can avoid wasting 6 liters daily, translating to an annual savings of about 2,700 liters of diesel. Assuming diesel costs 7 RMB per liter, this equates to over 2700USD in yearly savings. Beyond cost reduction, minimizing idle time decreases carbon emissions, aligning with stringent environmental standards.
What Refrigerant Charging Means for the VS02 Pro
Refrigerant charging refers to the process of adding the correct amount of R410A to the sealed system of a parking air conditioner after installation or repair. The VS02 Pro is a 12V or 24V DC rooftop unit that cools with R410A, which provides about 20% higher cooling than an R134a system and roughly 25% power savings. Charging must be done to the manufacturer specification, because an undercharged system loses capacity and an overcharged system trips the compressor.
Because the VS02 Pro runs entirely from the battery bank, every watt matters. A correctly charged unit reaches its rated 2800 W of cooling capacity and supports up to 18 hours of runtime, with a typical pattern of 6 hours during the day and 12 hours at night. A system that is only slightly undercharged can quietly eat into that runtime without triggering an obvious fault.
How to Charge Refrigerant Safely
- Step 1: Recover and vacuum. Recover any remaining refrigerant, then pull a deep vacuum on the system to remove moisture before charging begins.
- Step 2: Weigh in the charge. Charge R410A by weight using a digital scale, never by guesswork, and follow the charge printed on the unit nameplate.
- Step 3: Verify pressure and cooling. Run the unit and confirm stable suction and discharge pressures, then check the supply air temperature before handing the vehicle back.
FAQ
Q: Can I charge R410A myself?
A: Refrigerant charging requires recovery equipment and a license in most regions. Have a qualified technician perform the charge in about 2 hours to protect the compressor and the warranty.
Q: How do I know if the charge is low?
A: The classic signs are weak cooling, longer run cycles and a compressor that cycles on and off. If runtime falls noticeably below the expected 18 hours, check the charge before blaming the battery.
Updated: 2026-05-19 · By Vethy Technical Team
Common Charging Mistakes to Avoid
Most refrigerant problems on a VS02 Pro trace back to one of three mistakes. The first is charging by pressure alone: R410A must be weighed in, because pressure readings shift with ambient temperature and can hide a 100-gram error that quietly saps capacity. The second is skipping the vacuum, which leaves moisture in the loop and turns into acid once the compressor runs. The third is reusing mixed refrigerant, which changes the blend ratio and throws off the 20% higher cooling versus R134a that the system is engineered around.
A correctly charged unit holds its rated 2800 W of cooling and delivers up to 18 hours of runtime, matching the 6 hours by day and 12 hours by night pattern. If runtime falls short of that, check the charge before the battery. A technician can recover, vacuum and recharge the system in about 2 hours, and fleets should re-verify cooling performance on the same 90-day cadence they use for the rest of the truck.
The Tools a Correct Charge Requires
A precise charge depends on a short list of tools: a recovery machine, a vacuum pump with a micron gauge, a digital refrigerant scale and an R410A manifold set. The scale matters most, because R410A is charged by weight and the tolerance is tight. A system charged correctly reaches its rated 2800 W of cooling and holds up to 18 hours of runtime, following the 6 hours by day and 12 hours by night pattern that the VS02 Pro is built for.
After charging, confirm the result rather than trusting the gauge alone: check the supply air temperature, the compressor current draw and the pressure readings against the nameplate. On a fleet, repeat that check on the same 90-day cadence used for over-the-road trucks and the 30 to 45-day cadence for regional trucks, so a slow leak is caught before it eats into runtime.