Views: 0 Author: Site Editor Publish Time: 2026-09-04 Origin: Site
Multi‑purpose fruit warehouse handles different climacteric fruits: banana, avocado, tomato, mango, kiwi. One cold room may switch between storage mode and ethylene ripening mode for various products. The air cooler must support switchable setpoints for temperature, evaporating temperature and RH, adapt to different fruit requirements.
Fruit | Room Temp Range | Evaporating Temp Te | Coil ΔT | Target RH | Main Risk |
|---|---|---|---|---|---|
Banana | 13‑19 °C | 7~12°C | 5‑7K | 90‑95% | Chilling injury <12°C, weight loss |
Avocado | 7‑18 °C | 3~11°C | ≤5‑6K | 90‑95% | Chilling injury <5°C, high respiration heat |
Tomato | 12‑21 °C | 6~15°C | ≤6K | 88‑92% | Mould if RH＞93%; chilling <10°C |
Mango | 12‑22 °C | 7~14°C | ≤6K | 85‑90% | Skin spotting, over‑high RH causes rot |
Key design note: Multi‑fruit warehouse cooler must use oversized small‑ΔT coil. It can run higher evaporating temperature for high‑humidity ripening; avoid running large ΔT which dries air.
Evaporator Coil
Oversized coil design for small ΔT operation across all working modes.
Tube: Copper tube; upgrade to SUS304 tube for coastal / frequent wash pack‑house.
Fin spacing: 4.5‑5.0 mm, anti‑frost‑bridging.
Standard: Hydrophilic aluminium fin.
Corrosive environment option: Epoxy‑hydrophilic composite coated coil (resist fruit volatile acid, salt mist, cleaning detergent).
EEV electronic expansion valve is mandatory: enables continuous adjustable evaporating temperature for different fruits. Fixed‑orifice capillary cannot satisfy multi‑product switching.
Fan System
Preferred: EC 0‑10V variable‑speed axial fans, IP54/IP55.
Adjustable air velocity: 0.5‑1.5 m/s, set different fan speed for different fruits.
Avocado / banana: low speed (0.5‑1.0 m/s) to prevent shrinkage
Tomato / mango: moderate speed (0.8‑1.2 m/s) to avoid mould
High air change rate (60‑110 ACH) for uniform temperature & ethylene gas distribution.
30‑50% energy saving vs AC fans; no frequent start‑stop cycling.
AC two‑speed fans only for low‑budget small warehouse; limited flexibility for multi‑fruit switch.
Defrost System
Hot‑gas defrost (strongly recommended for multi‑fruit warehouse) Mild defrost process, minimal T&RH fluctuation, suitable for high‑humidity ripening conditions for banana / avocado.
Electric defrost: only acceptable for small unit; defrost time must be short, risk of RH drop for high‑humidity fruits.
SUS304 insulated drain pan + heat‑traced drain pipe. Prevent condensate dripping onto fruits and re‑freezing.
Casing & Housing
SUS304 stainless steel casing or anti‑corrosion painted galvanized steel; food‑grade, easy‑clean for fruit warehouse.
Control & Logic (Multi‑fruit critical feature)
PLC controller with multiple fruit preset profiles: Banana / Avocado / Tomato / Mango.
Each profile auto‑loads: room temperature setpoint, evaporating temperature target, RH limit, fan speed range, defrost interval.
Linked with ethylene generator, temperature & humidity sensors.
Low‑temperature alarm for chilling injury protection for each fruit type.
