How to choose a refrigeration unit for a vehicle?

Violation of the temperature regime during the transportation of perishable goods leads to the write-off of entire shipments and penalties from retailers. The discrepancy between the capacity of the climate control equipment and the volume of the insulated van makes the refrigerator useless.
The design of the cooling system is based on thermal engineering calculations and analysis of logistics routes. The type of drive and the cooling capacity of the unit must compensate for heat flows through the body walls at peak external temperatures.
Choosing the type of refrigerator drive
Installations with direct drive from the car engine are mounted on low-tonnage commercial vehicles. The compressor is connected by a belt drive to the crankshaft of the motor. This scheme is effective for bodies with a volume of up to 30 cubic meters, carrying out urban transportation.
Autonomous diesel systems are installed on heavy-duty semi-trailers of mainline tractors. Its own internal combustion engine rotates the compressor independently of the operation of the main motor of the truck. This allows you to maintain the set temperature during parking at customs terminals.
When selecting a power source, it is necessary to take into account the specifics of the logistics chain.:
- eutectic plates are suitable for ice cream delivery with frequent door opening;
- generators from the power take-off shaft are optimal for medium-duty trucks;
- multi-temperature systems with independent evaporators solve the problems of bulk cargoes.
The use of an electric parking unit reduces the wear of the unit's diesel engine during night parking on warehouse ramps. The equipment is connected to a three-phase 380 volt network.
Calculation of cooling capacity and insulation
The compressor power is selected taking into account the coefficient of thermal conductivity of the van walls. Insulated booths made of sandwich panels 80 mm thick with extruded polystyrene foam minimize heat loss. If the heat transfer coefficient exceeds 0.4 Watts per square meter, the equipment will wear out.
The volume of the body determines the required air exchange rate. The evaporator fans must disperse the entire volume of air in the van at least 60 times in one hour. A weak airflow creates blind spots in the tail section of the trailer, where the load begins to deflate.
For an accurate engineering calculation, input data on the type of products being transported is required:
- deep freezing requires stable maintenance of minus 20 degrees;
- chilled meat is transported in the range from zero to two degrees;
- fresh greens need humidity control and ethylene ventilation.
The power reserve of the installation must be at least 25 percent of the calculated value. This delta compensates for heat flows when the gates are opened during loading and unloading operations on the overpass.
Controls and service functions
Microprocessor controllers in the driver's cabin provide continuous monitoring of climatic parameters. Digital thermal recorders record the temperature every five minutes and print a receipt for the recipient. This serves as legal proof of compliance with the conditions of the cold chain.
The automatic defrost function of the evaporator with hot gas prevents the heat exchanger from freezing. The accumulation of an ice coat on the condenser fins blocks the circulation of freon and causes an emergency shutdown of the system due to a pressure surge.
The availability of spare parts and the density of the network of service centers directly affect the profitability of transportation. Failure of the temperature control valve away from the repair base is fraught with damage to 20 tons of products. The choice of common brand units reduces the risks of prolonged downtime. Finding an online betting platform with attractive introductory rewards is important for many Indian users who want to maximize the benefits of their first deposit. During the registration process, the 1xbet promo code for registration in india gives eligible players access to a casino welcome package up to ₹163,500 and 150 free spins, creating additional opportunities to explore featured casino games.