Topchill DJ series is a standard air cooler designed for low-temperature refrigeration applications (below -25°C). With 9.0mm fin spacing (optimized for deep cold), it is part of the D-series (DL/DD/DJ) and works seamlessly with Freon refrigeration units. The DJ series features powder-coated or stainless steel casings, stainless steel electric heating elements, and high-pressure internal rotor fans, making it ideal for deep freezers, frozen food warehouses, and pharmaceutical low-temperature storage.
9.0mm fin spacing prevents frost blockage in low-temperature environments (<-25°C), maintaining heat transfer efficiency even in heavy frost conditions.
Cools down to -40°C (with cascade systems), suitable for storing ice cream, frozen seafood, and temperature-sensitive pharmaceuticals.
Powder-coated steel or stainless steel casing resists corrosion from cold, humid air, extending service life to 10+ years.
Stainless steel electric heating elements distribute heat evenly for fast defrosting, complying with FDA and GMP standards for food/pharmaceutical use.
Internal rotor fans (Weiguang brand) deliver high pressure and airflow (up to 36,000 m³/h), ensuring uniform cooling in large low-temperature warehouses (50-300㎡).
Mechanical expansion bonds copper tubes tightly to aluminum fins, enhancing heat transfer efficiency by 15% compared to riveted designs.
Meets national energy-saving standards, reducing electricity costs for 24/7 deep-freeze operation.
Low maintenance requirements—stainless steel components resist wear, minimizing replacement costs.
Instruction manual
Air coolers
I. Overview
Air cooler (also called chiller) is a kind of cooling equipment suitable for various cold storage, Chengdu Tianqi air cooler has three types of 4.5-pitch, 6-pitch and 9-pitch, which are respectively suitable for cold storage of different storage temperature. It has the advantages of compact structure, light weight, not occupying the practical area of the cold storage, etc. Compared with the natural convection exhaust pipe, it can make the food stored in the cold storage cool down quickly, and greatly improve the freshness of the stored food.
II. Product use
Chengdu Tianqi air cooler can be used as refrigeration equipment with different refrigeration capacity of compression condensing unit for cold storage of different temperature. The 4.5-pitch air cooler is suitable for the cold storage with the temperature of 0℃, such as the storage of fresh eggs or fruits and vegetables, and the 6-pitch air cooler is suitable for the cold storage with the temperature of -18℃ as the cold storage of meat, fish and other frozen foods, and the 9-pitch air cooler is suitable for the cold storage with the temperature of -25℃ or below-25℃ as the freezing of fresh meat or fresh fish products and seasoned foods.
Ⅲ. Product features
1、The shell is made of plastic spraying steel plate, rolled aluminum plate or stainless steel plate, which is corrosion-resistant and beautiful in appearance, and can meet the needs of different customers.
2、The coils are arranged in the way of rows or fork rows, which can be selected according to different usage environments, and the heat transfer efficiency is high.
Aluminum fins are set on copper or aluminum tubes and connected firmly.
3、The product is wired in the factory, and all the fan wiring is placed in a junction box, which is convenient for installation and maintenance.
4、The motor and wind blade are selected for low noise, smooth operation and explosion-proof motor according to users' needs.
5、Drainage pipe is equipped with drainage interface at the lowest place in the center, reliable drainage.
6、Tubular stainless steel tube and magnesium oxide filler electric heating tube, placed in the coil, the effect of frost melting is good, several optional frost melting method (electric heating tube, water, hot air).
7、All of them have been processed with nitrogen before leaving the factory.
IV. Precautions
1. Please read the precautions in the document carefully before use.
2. Personal protective equipment should be equipped when operating this equipment, such as: gloves, glasses, protection.
3. Avoid touching the edges of the sheet metal and the fins of the coiler, the sharp edges may cause injuries.
4. All on-site wiring must comply with industry code standards and national and local codes. For any maintenance service or point up operation must first cut off the power supply, is strictly prohibited to operate with electricity.
5. Before starting the machine, the professional and technical personnel should verify whether the electrical parameters of the equipment match with the actual use of the power grid.
6. Should confirm that the equipment circuit and refrigeration system electrical protection device is normal and intact before the equipment can run. Equipment should be installed reliable grounding protection.
7. In the daily maintenance and repair work, wear eye protection and gloves, and be very careful handling of refrigerant, to avoid inhalation and contact with refrigerant, otherwise it may lead to blindness or other injuries or even death.
8. When installing and operating the equipment, it should be far away from high temperature open fire and corrosive substances, and there should be no combustible and explosive materials around the equipment to prevent fire and other accidents.
9. Correctly adjust the direction of air outlet of the chiller.
10. The chiller has been filled with high-pressure nitrogen when it is shipped from the factory, and can only be installed and used when the nitrogen is emptied.
11. The daily maintenance and repair work must be carried out by the corresponding professional technicians, in addition to cleaning, should focus on the electrical heating
In addition to cleaning, should focus on the electric heating tube, fan and other electrical reliability, safety, regular inspection and testing and record, found abnormalities should be promptly excluded afterOnly then can it be operated.
WARNING
1. It is strictly prohibited to insert any object into the fan during operation to avoid injury to personnel and damage to equipment.
2. In order to ensure the safety of the user and the correct use of the product, it must be operated by a professional (refrigeration serviceman/electrician),
Installation and maintenance. The operation must be equipped with personal protective equipment, otherwise the company does not provide quality assurance, and does not assume any legal responsibility for the resulting accidents.
Otherwise, the company does not provide quality assurance and does not bear any legal responsibility for the accidents caused.
3. When the chiller adopts electric heat to tolerate frost device, it must be installed with overheat protection device for frost melting temperature before use to ensure the safety of use.
4. Avoid direct contact between the skin and the operating equipment (refrigerant or piping); avoid possible frostbite or scalding.
5. equipped with electric heat defrosting device of the chiller, 18 months from the factory date, the customer should be regularly on the use of the performance of the electric heat pipe and the safety performance, insulation performance test, found abnormalities immediately replace the maintenance before use. Otherwise, the company will not assume any legal responsibility for the adverse consequences caused by this.
6. When the heating tube exceeds the normal service life, it should be replaced in time in order to eliminate potential safety hazards.
7. It is strictly prohibited to use oxygen to keep pressure on the chiller. 8.
8. There should be no bare insulation material within 2.0 meters around the chiller, and it must be veneered with metal material. Avoid electrical sparks generated by electric heaters, terminal aging, etc. and ignite the insulation materials in the warehouse.
9. Conventional chillers are strictly prohibited to be used in an environment with flammable and explosive materials. (Except for special design)
V. Installation of the chiller
1. When unpacking, check that the equipment and packing materials are not damaged; any damage may affect the operating results. If you find any obvious damaged parts, please contact our company.
2. For chiller installation, please refer to the installation dimension drawing.
3. Users should use suitable equipment to lift the product to the appropriate position according to the weight of the purchased item.
4. Freon ceiling type chiller can be lifted on the roof plate of the warehouse with 4, 6, 8 or 10 long bolts. A single steel M8 bolt and nut can withstand a weight of up to 110kg and M10 can withstand a weight of up to 270kg.
5. The distance between the ceiling-mounted chiller and the wall should be maintained at 250~350mm (see the right figure), so as to facilitate the circulation flow of cold air in the cold storage and maintenance.
6. After installation, the ceiling-type chiller should be guaranteed to be level.
7. The drain pipe of the chiller should have a certain slope to the outside of the cold storage, so that the frost water can be smoothly discharged out of the library, and the connecting pipe outside the library should be curved into a U-shape, and the pipe should ensure a certain degree of liquid sealing in order to prevent a large amount of hot air outside the library from entering into the cold storage (see the figure).
8. In the cold storage of the drain outside should be insulated, the library temperature is lower than -20 ° C, the drain pipe should be added to the electric heaters to prevent frost water in the process of water leakage icing.
9, in order to achieve the best refrigeration effect, the thermal expansion valve should be installed as close as possible to the liquid separator position.
10. When installing the expansion valve, the temperature sensing package must be tightly tied in the upper part of the horizontal return pipe (suction pipe diameter ≤ 25) or the lower part of the 45 ° diagonal down (suction pipe diameter ≥ 25), and to ensure that the contact with the return pipe is good, outside the return pipe should be insulated to prevent the temperature sensing package affected by the temperature of the library.
11. The external balance pipe is used to connect the external balance port of the thermal expansion valve and the top of the horizontal suction pipe near the suction manifold. Connected to the suction pipe of 1/4 inch copper pipe is said to be the external balance pipe.
12. The chiller outlet should avoid the beam-type column so as not to affect the range of the air supply.
13. In order to ensure that the chiller achieves optimum heat transfer, the distributor must be mounted vertically to ensure that the refrigerant is evenly distributed to the various refrigeration circuits.
14. The design and installation of the refrigeration pipeline must be designed and installed by professional refrigeration technicians in accordance with national and local norms, and at the same time conform to the good refrigeration engineering operation.
15. The cleanliness of the chillers provided by our company is in line with the requirements, and the interior is pre-filled with dry nitrogen to prevent oxidation and the entry of moisture and external impurities. When installing, try to shorten the time that the receiver is exposed to the air to prevent the entry of external impurities and moisture.
16. The refrigeration connection piping does not have to be the same as the outlet piping of the chiller, and the selection and calculation of the piping size should be based on the principle of minimum pressure drop and flow rate attenuation.
17. Horizontal suction pipes need to leave the chiller at a certain inclination to ensure that the refrigerant oil is returned to the compressor by gravity. an inclination of 1:100 is sufficient. When the suction pipe is higher than the chiller, it is advisable to install an oil return bend.
18. When removing the chiller from its original installation position, it must be dismantled by a professional refrigeration technician, who should first cut off the power supply, remove all the unwanted field wiring, the corresponding electrical components, and then cut off the ground wire; cut off and seal the joints of the liquid pipe and the gas pipe, disconnect the drain pipe, and remove the chiller. Be sure to follow the above procedure when operating. Failure to follow this procedure will result in injury or death to the operator and property damage due to fire or explosion. Venting refrigerant directly into the atmosphere is illegal and can result in severe fines from the monitoring authority.
19. In order to equalize the pressure between the evaporator and the outside world, special care must be taken when opening the needle valve spool. A certain amount of refrigerant is dissolved in the lubricating oil and when the pressure of the chiller rises the refrigerant boils and evaporates, which may result in injury.
20. If the equipment is not to be used for a longer period of time, pump the entire charge of refrigerant back into the reservoir or into a suitable reservoir (refrigerant cylinder).
VI. Electrical connection of the chiller
1. All electrical connections must follow the appropriate specifications and be implemented by a professional electrical technician.
2. Electrical connection diagram
Ⅶ. Chiller commissioning guidelines
1. The start-up commissioning of the refrigeration system needs to be in line with the correct refrigeration operation reality and should be operated by a certified refrigeration mechanic.
2. Due to transportation may lead to loose factory wiring, please reconfirm the factory wiring and the wiring on site. Check whether the running direction of the fan motor is correct, and whether the airflow is drawn in from the coil and discharged from the fan side.
3. Check whether the thermostat of the storage room is running normally, and adjust the parameters if necessary.
VIII. Defrosting guide for chillers
In order to enable customers to get the most efficient and maximum airflow when using our evaporators, it is recommended to defrost according to the following defrost parameters.
Saturated suction temperature | -30 | -24 | -18 | -12 |
Number of defrosts at maximum temperature difference | 7 | 7 | 6 | 6 |
Number of defrosts for temperature differences | 5 | 4 | 4 | 4 |
Number of defrosts withe minimum temperature difference | 4 | 3 | 3 | 4 |
The recommended defrost time (-18°C cold storage) is adjusted according to actual usage.
Difference in temperature | Light duty | Heavy duty | Light duty | |||||
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | |
10 | × | × | × | × | × | × | × | |
8 | × | × | × | × | × | × | ||
6 | × | × | × | × | ||||
4 | × | × | × | |||||
Note: Each column represents 3 hours of the daily time period. The “x” shows when defrost should start. “Heavy Duty” shows the ‘work phase’ of the day in the usual sense.
Defrost Termination Requirements
The average defrost time for a normally loaded system is approximately 20-25 minutes (including drip time). This defrost time can vary with the degree of frost buildup.
Time Out - The time out is set to ensure that the coil is defrosted even under the heaviest loads. Typical time settings are 25-30 minutes with a safety shut-off time of 35 minutes.
Temperature termination - The temperature termination is set depending on the frequency of defrosting and the condition of the frost, but also on the position of the temperature sensor/temperature switch. If an electronic defrost controller is used, the set point for temperature termination must be determined individually for each chiller in the installation environment. The set point is generally around 15°C for the chiller outlet air duct for example.
Electric heating tube overheating protection - The standard products of the chiller produced by our company do not come with heating tube overheating protection device. The customer is responsible for installing a suitable protection device to prevent damage to the chiller and fire and other accidents caused by excessive temperature and pressure in case of controller and sensor failure.
Fan Delay Requirements - Fan delays will vary depending on the application, but in general should not exceed 5 minutes.
IX. Routine maintenance of equipment
Depending on the normal operating conditions and bad conditions, after successful commissioning, a maintenance schedule should be prepared to ensure that the chiller operates at optimum efficiency while keeping operating costs to a minimum. When doing maintenance, check and record the following parameters:
1)Check the chiller for corrosion, abnormal vibration, oil plugging and dirty and clogged drain pipes, which need to be cleaned frequently with soapy water.
2)Clean the fins of the chiller with a soft brush, rinse the coil with low pressure water or use special coil cleaner. Acidic cleaners are prohibited. Follow the labeled instructions for use. Rinse the coil until there is no residue.
3)Check each motor fan for proper rotation, fan cover for blockage, and loose bolts.
4)Check wires, terminals and other components for damage, loose wiring, and blackened components with burn marks.
5)Check whether all the coil heating tubes are in the original position, whether they are firmly installed, check whether the heating tubes of the water accumulation coil are in good contact with the tray and whether the position is on the bracket.
6)Check whether the frost on the coil on the exhaust side is even during operation. Uneven frosting indicates that there is a blockage in the dispensing head or the refrigerant is not charged correctly. Possible superheated gas on the coil at the suction side without any frosting.
7)Adjust the defrost cycle according to the abnormal frost condition.
8)Check the superheat level and adjust the human expansion valve accordingly.
9)The power must be disconnected during cleaning and maintenance (electrified operation is strictly prohibited), and the water accumulation disk is also a component that needs to be repaired, and there is a hidden danger if the chiller is operated without installing the water accumulation disk.
