How to Select Suitable Copeland Units for Fruit Cold Storage 2

Key Warning for Model Distinction

Copeland ZF and ZSI series are special low-temperature freezing models, only applicable to freezing cold storage below -18℃. They are strictly prohibited for all fruit fresh-keeping cold storage. When low-temperature models operate under medium and high temperature working conditions, energy efficiency drops sharply, power consumption surges, and frequent start-stop will seriously disrupt the temperature and humidity balance of cold storage.

2. Accurately Calculate Cooling Load to Determine Unit Horsepower Scientifically

 Unit horsepower is the core parameter for selection. The empirical algorithm of matching horsepower only

1. Low-temperature

by cubic volume cannot adapt to actual working conditions with large incoming volume, high ambient temperature and frequent door opening, which may easily cause equipment overload or excessive margin. Accurate model selection requires three steps: load calculation, correction coefficient and safety margin.

(1) Reference for Basic Cooling Load (Standard Insulation Working Condition)

Based on standard cold storage with 100mm polyurethane national standard insulation panels and good tightness:

fresh-keeping cold storage at 0～4℃: 70～100W/m³;

2. Medium-temperature fresh-keeping cold storage at 4～10℃: 60～80W/m³;

3. Constant temperature cold storage for tropical fruits at 12～15℃: 50～70W/m³.

(2) Correction Coefficient for Actual Working Conditions

Superpose corrections combined with cold storage operation scenarios to fit actual application demands:

1. Wholesale markets for fruits and vegetables, frequent loading and unloading, long-term open warehouse doors: ×1.15～1.3;

2. Regions with high temperature in summer, poor ventilation of condensers and exposure to sunlight: ×1.1～1.2;

3. Centralized warehousing of large quantities of fresh fruits without pre-cooling warehouse, large instantaneous heat load: add an extra 20% cooling capacity;

4. Newly built cold storage with undried walls and floors and high humidity: ×1.1.

(3) Principle of Safety Margin Reservation

After the cooling load calculation is completed, a safety margin of 10%～20% shall be reserved uniformly. Insufficient margin will lead to difficulty in temperature reduction in hot summer, 24-hour full-load operation of units and accelerated equipment aging. Excessive margin will cause frequent start-stop of units, excessive fluctuation of warehouse temperature, resulting in fruit water loss, cold damage and shriveled peel.