HVAC Case Study
Alpha Pharm Distribution Centre

The 24/7 and approximately 4,500m² Alpha Pharm facility in Pretoria incorporates a mezzanine level and double packing capacity. It has been in operation since 1992 and distributes anything from 70,000 to 135,000 single items per day, depending on the orders. On a normal working day, it has about 100 people on the floor. The night shift has around 40 people working after hours. The facility holds about 16 000 different product lines in stock at any one time.

In keeping with international standards and legislation, Alpha Pharm’s management chose to modify their distribution centre in Pretoria by replacing its ageing single-stage evaporative cooling system with a more suitable (and beneficial) Climate Wizard indirect evaporative cooling solution.

Project Requirements

The DC’s existing system comprised 20 single-stage evaporative coolers. Many were insufficient to achieve the optimal desired conditions for the warehouse. The issue of dust in the facility also had to be considered seriously. This was causing wear and tear on the massive robotic picking machine.

Alpha Pharm gave the Crown Technologies team the following brief:

• The facility’s temperature was not to exceed 25°C.
• The system had to have a low running cost.
• Low cost of ownership.
• The facility was to have a positive pressure to prevent dust ingress with filtered air.
• No increase in the moisture content of the air, as this would have a negative effect on the packaging materials.

Solution

The Crown team did their research, identifying Seeley’s Climate Wizard indirect evaporative cooling system as the perfect solution.

Each of the four sections of the facility has five dedicated Climate Wizard CW-H15 coolers, each with their own control.

The main benefit of using Climate Wizard is energy efficiency now operating costs), with no additional humidity. This was an essential consideration, as the humidity would affect the packaging of many of the products, negatively impacting their integrity.

Results

• The matter of positive pressure inside the facility limits dust coming into the facility (although there is no way to completely get rid of it).
• The client noted that when they retrofitted one of their other facilities with a more conventional HVAC system, there was a noticeable difference in electricity usage. Their electricity cost increased by approximately RS0 000 a month, whereas with the Pretoria facility, the increase was miniscule in comparison.
• The temperature specification was also more than achieved as the team found that they could achieve a consistent 22°C as opposed to the 25°C that was requested. This meant that they did not have to run all the machines all the time resulting in lower running costs.
• The new solution also uses less water than the previously installed evaporative cooling system. This is because the indirect system does not have water constantly running over the cooling medium but only flushes over it one minute out of every eight.
• In addition, there was no need for a fresh air component to the air-conditioning system as the Climate Wizard always supplies 100% fresh air. Therefore, the building will always be pressurised.
• Installing strip curtains over all exits has also helped to control the loss of cool clean air from the building.
• Another benefit of this system is that the power usage does not increase as the outdoor temperature increases, as with conventional refrigerated air conditioning. This is a result of the elimination of refrigerant gas compression.
• The very low maintenance cost of the system is the result of few moving parts and no compressors, gas charges and the like that could become faulty.

Learn more about Seeley International’s range of indirect evaporative coolers.