Cold room doors remain of interest to Barpro, as those which remain open or don’t seal properly can cause a shim of ice on the cold room floor preventing mobiles from operating efficiently. In 2016, Barpro discussed the importance of freezer store entrances.
More importantly, cold store doors play a critical role in the efficient operation of a freezer store:
- Doorways are the biggest escape routes for cold air and access for warm air which coats evaporators with ice lowering refrigerant efficiency and rising energy costs.
- Spending more on a door system which reduces air movement can be a good investment with ever-rising of electricity costs.
Cold or Freezer store operators often find it difficult to select the appropriate door for their operations. Let’s look at the scenario below:
Some years ago, a UK cold store owner stated that the electricity usage difference between a 30,000 and a 15,000-pallet freezer store was just over £1500 per year so long as both had one properly protected doorway.
The doors designed by this UK store are just under 3 meters high and wider than the South African standard of 2.4 meters, with a demarcation line in the middle and entry on the left. Reach truck access is via a separate door. The freezer entrances have clear plastic flaps, not strip curtains, and an interior airlock with a dehumidifier that exerts a positive air pressure.
What are the pros and cons of traditional freezer doors?
Worldwide, the traditional approach to industrial refrigeration spaces is to install heavy insulated door with a high R- Value. This R-value is the measurement of resistance of a material to transfers heat. This is the measure of quality and performance of the insulation.
Other traditional approaches include inexpensive strip curtains and air curtain systems. This solution has a low R-value and that can cause ice build-up on the strips and floor. The low upfront cost is very appealing, but it defeats the purpose of sealing the freezer, which will become a huge expense in the long run.
On top of this is the damage that can be caused by ice inside freezer stores; from machines slipping on icy floors to water; from malfunctioning, evaporator drip trays contaminating the stored product.
The Australian solution is to have high-speed doors cut down moisture ingress by up to 99% over PVC strip curtains while reducing energy losses by the same margin. They can be installed either in or outside the freezer door entrance can be made of an insulated closed-cell material that removes the need for a traditional sliding “night” door.
Different types of cold or freezer store doors to consider
