An open chiller is a refrigerator without a lid: it tries to hold cold air in with an air curtain and continuously cools part of the store's air. A night blind closes that opening while the store is shut. The gain is looked for in two places: the electricity drawn overnight and the product temperature at opening. The cost of a blind is habit rather than money; left off the closing checklist it is forgotten within weeks and stays rolled up.
- Night electricity: kWh from closing to opening, same cabinet
- Morning product temperature: same shelf, same product, same method
- Conditions: store hours, outside temperature, replenishment frequency
Log one week with and one week without the blind and compare similar days. Because the result varies with cabinet type, store ventilation and closing time, your own figure is used instead of a general percentage. Add the blind to the closing checklist, check the mechanism monthly and replace a torn blind at once: a jammed blind does not get pulled and nobody reports it.
