WKDL Industrial & Marine Air Coolers
Authorized distributor of WKDL evaporators — 6 series, 66 models covering cold storage, food processing, logistics centres, and marine refrigeration. From medium-temperature ceiling coolers to ultra-low-temperature blast freezers.
CE Certified
ISO 9001
WKDL Air Coolers — The Complete Range for Cold Chain & Marine Refrigeration
Air coolers (also called unit coolers or evaporators) are the terminal heat exchange units in any refrigeration system. Installed inside cold rooms, freezer chambers, processing halls, and marine cargo holds, they absorb heat from the ambient air and transfer it to the circulating refrigerant. The selection of the right air cooler — capacity, fin spacing, defrost method, airflow pattern, and material construction — determines the system’s cooling performance, energy efficiency, and product quality.
hicool is an authorized distributor of WKDL air coolers, one of China’s leading manufacturers of industrial evaporators. WKDL produces over 10,000 units annually, serving cold storage operators, food processors, logistics companies, and marine refrigeration contractors across Asia, the Middle East, Africa, and South America. Their product line covers six distinct series, each engineered for specific application conditions — from +5°C fresh produce storage down to -45°C blast freezing.
As an authorized channel, we provide factory-direct pricing, full technical support, and warranty coverage. All units ship with CE certification, test reports, and comprehensive installation manuals. Custom configurations — non-standard voltages, special coatings, extended headers — are available on request with 2–3 weeks added lead time.
Why WKDL Air Coolers
WKDL differentiates from generic Chinese evaporator manufacturers through several key engineering choices:
- Copper tube + aluminium fin construction — standard across all series. Seamless copper tubes (TP2, 9.52/12/16 mm OD) mechanically expanded into aluminium fins for optimal thermal contact. No brazing at tube-to-fin joints means zero risk of fin loosening over time.
- Hydrophilic coating — factory-applied on aluminium fins to promote even water drainage during defrost, reduce ice bridging, and extend the interval between defrost cycles.
- Hot-dip zinc option (DDF series) — for corrosive environments (seafood processing, marine, high-humidity), the entire coil and casing are hot-dip galvanized after fabrication, providing 10+ years corrosion resistance.
- EC motor option — energy-efficient electronically commutated fans available across all series, reducing fan power consumption by 30–50% compared to standard AC motors.
- Wide capacity range — from 1.5 kW (small walk-in cooler) to 120+ kW (large distribution centre) in a single manufacturer’s range, simplifying multi-zone projects.
Application Sectors
Cold storage & logistics — the primary market. DL ceiling coolers for medium-temperature rooms (+2°C to -5°C), DD floor coolers for low-temperature freezer rooms (-18°C to -25°C), and KFS blast chillers for rapid product cooling. Fin spacing and defrost method are matched to the room temperature: wider fins (9–12 mm) and electric defrost for freezer rooms, tighter fins (4–6 mm) and air defrost for medium-temp rooms.
Food processing — processing halls, cutting rooms, packaging areas. DLS side-blow coolers provide horizontal air distribution across large floor areas without ceiling-mount requirements. DDF hot-dip zinc coolers resist the corrosive atmosphere of seafood and meat processing facilities.
Marine refrigeration — provision cold rooms, fish hold cooling, reefer container pre-cooling areas. Marine installations require corrosion-resistant construction (DDF series or epoxy-coated coils), compact dimensions for tight shipboard spaces, and compatibility with marine-grade electrical supply (440V/60Hz).
Pharmaceutical & chemical cold storage — controlled-environment storage rooms requiring precise temperature uniformity. DL series with EC fans and electronic expansion valves provides ±0.5°C temperature stability.
The 6 WKDL Series at a Glance
Each series is purpose-designed for a specific installation scenario. The comparison table below summarises the key differences — click through to each series page for detailed model specifications, dimensional drawings, and selection guidance.
6 Series — Complete Product Range
DL Series — Ceiling Coolers
Medium and high temperature. Ceiling-mounted, top-blow. For fresh produce, dairy, beverage, and pharmaceutical cold rooms. 2–80 kW.
DD Series — Floor Coolers
Low and medium temperature. Floor-standing with top discharge. For freezer rooms, ice cream storage, and meat processing. 3–120 kW.
DJ Series — Low-Temperature Coolers
Ultra-low temperature (-25°C to -45°C). Wide fin spacing (12 mm) for heavy frost conditions. For deep-freeze storage and blast freezing.
KFS Series — Blast Chillers
High-velocity air blast for rapid product cooling. Tunnel and room configurations. For meat, seafood, bakery, and ready-meal chilling.
DLS Series — Side-Blow Coolers
Horizontal air discharge for large processing halls and workshops. Wall-mounted, no ceiling structure required. Uniform temperature distribution.
DDF Series — Hot-Dip Zinc Coolers
Full hot-dip galvanized construction for corrosive environments. Seafood processing, marine, coastal, and high-humidity applications. 10+ year coil life.
Series Comparison — How to Choose
| Series | Mounting | Airflow | Temp. Range | Fin Spacing | Defrost | Capacity | Best For |
|---|---|---|---|---|---|---|---|
| DL | Ceiling | Top-blow (vertical down) | +5°C to -5°C | 4 / 4.5 / 6 mm | Air / Electric | 2–80 kW | Fresh produce, dairy, pharma |
| DD | Floor | Top discharge | -18°C to -25°C | 6 / 9 / 12 mm | Electric / Hot gas | 3–120 kW | Freezer rooms, meat, ice cream |
| DJ | Ceiling / Floor | Top-blow | -25°C to -45°C | 9 / 12 mm | Electric / Hot gas | 3–80 kW | Deep-freeze, blast freeze |
| KFS | Floor / Tunnel | High-velocity horizontal | -30°C to -40°C | 9 / 12 mm | Electric / Hot gas | 15–100+ kW | Rapid chilling, IQF tunnel |
| DLS | Wall | Horizontal (side-blow) | 0°C to -25°C | 6 / 9 mm | Electric / Hot gas | 5–60 kW | Processing halls, workshops |
| DDF | Ceiling / Floor | Top-blow / Top discharge | -5°C to -35°C | 6 / 9 / 12 mm | Electric / Hot gas | 3–80 kW | Seafood, marine, coastal |
Selection tip: Start with the room temperature requirement to narrow down the series, then use mounting type and airflow pattern to finalize. For projects with multiple zones at different temperatures, we often combine DL (fresh) + DD (frozen) + KFS (blast) in a single supply package.
Engineering Details
Coil Construction
All WKDL air coolers use seamless copper tubes (TP2 grade, per ASTM B75) mechanically expanded into aluminium fins. Standard tube diameters are 9.52 mm (3/8″), 12 mm, and 16 mm (5/8″) depending on the series and capacity. Fins are punched from 0.2 mm aluminium sheet with hydrophilic coating applied before assembly. Tube circuits are designed for even refrigerant distribution using distributor-type headers.
Fan Systems
Standard fans are axial-flow type with external-rotor AC motors (IP54/IP65). EC (electronically commutated) motor upgrade is available across all series — EC fans reduce electrical consumption by 30–50% and allow stepless speed control for precise capacity modulation. Fan diameters range from 250 mm (small DL models) to 800 mm (large DD and KFS models). All fans are statically and dynamically balanced.
Defrost Systems
Three defrost methods are supported: Air defrost (natural or fan-assisted, for rooms above 0°C), Electric defrost (stainless steel heater elements embedded in the coil, standard for -18°C and below), and Hot gas defrost (using discharge gas from the compressor, most energy-efficient for large installations). Defrost water drain pans are insulated and electrically heated to prevent re-freezing.
Refrigerant Compatibility
WKDL coolers are compatible with R22, R134a, R404A, R507A, R407C, R448A, R449A, and R717 (ammonia). For ammonia systems, stainless steel tube construction replaces copper. Expansion valve connection type (thermostatic or electronic) is specified at order.
Custom Configurations
Beyond standard catalogue models, WKDL accepts custom orders for non-standard requirements: special voltages (440V/60Hz marine, 220V/60Hz export), epoxy-coated coils (blue or black), extended headers for field piping, and non-standard casing dimensions. Minimum order quantity for custom units is typically 5 pieces. Lead time: 4–6 weeks.
Recent Supply Projects
10,000 m³ Cold Storage Facility — Multi-Zone Cooler Package
Scope: 8 × DL ceiling coolers (+2°C fresh produce zone) + 12 × DD floor coolers (-22°C frozen zone) + 2 × KFS blast chillers (-35°C rapid cooling tunnel). Total cooling capacity: 480 kW.
Refrigerant: R507A
Lead time: 5 weeks
Seafood Processing Plant — DDF Anti-Corrosion Coolers
Scope: 6 × DDF hot-dip galvanized ceiling coolers for seafood processing hall (-5°C) and cold storage (-25°C). High-humidity, salt-air environment.
Refrigerant: R717 (ammonia) — stainless steel tube option
Lead time: 6 weeks (custom SS tube)
Logistics Distribution Centre — DLS Side-Blow for Dock Area
Scope: 4 × DLS side-blow coolers for loading dock temperature maintenance (+8°C) — wall-mounted, horizontal discharge to cover 2,400 m² dock floor area without ceiling fixtures.
Refrigerant: R404A
Lead time: 3 weeks (standard models)
Frequently Asked Questions
What does “authorized distributor” mean — do you carry stock?
As WKDL’s authorized distributor, we sell at factory pricing with full manufacturer warranty. Standard models (DL and DD series, common sizes) are typically available from WKDL’s finished goods inventory with 1–2 week lead time. Less common models and custom configurations are made to order in 3–6 weeks.
How do I select the right series for my cold room?
Start with room temperature: above -5°C use DL (ceiling mount) or DLS (wall mount). For -18°C to -25°C use DD (floor mount). For -25°C to -45°C use DJ or KFS. For corrosive environments (seafood, marine) use DDF regardless of temperature. Then match the cooling capacity to the room heat load calculation. Contact us with room dimensions, temperature, stored product, and daily throughput — we will provide a selection recommendation.
Can WKDL coolers be used with ammonia (R717) systems?
Yes. For ammonia systems, WKDL supplies coolers with stainless steel tube coils instead of copper (ammonia is incompatible with copper alloys). Stainless steel tube is a custom option — add 2–3 weeks to standard lead time. All other components (fins, casing, fans, defrost heaters) are the same as standard models.
What is the warranty period?
WKDL provides a 12-month warranty from date of commissioning (maximum 18 months from date of shipment) covering manufacturing defects in materials and workmanship. The coil is warranted against leakage. Fan motors carry the motor manufacturer’s standard warranty. Extended warranty is available on request.
Do you provide installation support and technical documentation?
Every unit ships with an installation manual, dimensional drawing, wiring diagram, and refrigerant circuit diagram. For large projects (10+ units), WKDL can provide on-site installation supervision at the buyer’s cost. We also provide selection software access and remote technical support for system design questions.
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