Case Studies

Cooling a laundry

Laundry equipment is energy intensive. The combination of dry cleaning and steam heated ironing processes lead to temperatures over 30°C in the working areas’. A total of 6 down discharge units were installed. A combination of plenum chambers and ducts were used to provide general coverage or spot cooling.

Extraction is provided through existing roof louvers plus some extract fans. Extractors are normally positioned at the highest possible level to remove the warmest air rising from the equipment. Extractors are placed a minimum of 6m from the coolers to prevent cross flow of hot air or any contaminants.

Laundries supplying hospitals are required to perform a risk assessment in implement controls to prevent microbiological cross contamination between dirty and clean laundry. This risk assessment is based on HACCP – Hazard Analysis and Critical Control Point.

A typical outcome of performing a HACCP analysis in a traditional laundry is the physical segregation of the two areas of the laundry with additional walls and the requirement to keep external doors closed.

A direct result of this is the deterioration in working conditions for the operators as the natural ventilation is removed.
A hot day in the UK is 25°C/50% Relative Humidity. In these conditions an EcoCooler would reduce the air by 7°C. At a nominal flow rate of 14,000m 3 /hr an evaporative cooler would use 60L/hr of water and would produce a cooling effect equivalent to 32KW from 1.5KW of electricity consumption.

Printers

Specialist printer of laminates using gravure and flexo web printing processes the factory produced packaging for the bakery, cereals, confectionery, dairy, ice cream and snacks markets.

The factory had an existing ventilation system but this was unable to maintain a comfortable working temperature. Following a trial of a single unit a complete factory proposal was designed using AutoCAD.

The details of the proposed cooler positions were then clearly and easily communicated to all interested parties. Fourteen internal evaporative coolers were installed at various locations throughout the factory.Each is individually controlled to give spot cooling to work stations both by the main printing presses and finishing areas.  The coolers are suspended from the roof structure using simple Unistrut components.All services run from above.

The mains water is supplied via brominators to provide a low level of biocide in the circulating water. The other use of internal evaporative coolers in the print industry is for humidification. During the summer months the Relative Humidity routinely drops below 30% in factories. In winter, when the air is being heated, the humidity can drop below 20%. An internal evaporative cooler can be used to control the minimum level of humidity in a print factory by connection to a hygrostat which will then control the fan speed and water circulation to achieve a minimum set point.

Fitness Centres

Typical fitness centre there is a demand for cool, comfortable conditions for exercise. The fresh air brought in by an evaporative cooling system produces a more comfortable environment than that produced by a re-circulating air conditioning system.

‘Sweat and body odours are removed and available oxygen levels are maintained which further contribute to maintaining the ideal conditions for exercise’

Down discharge, roof mounted, evaporative coolers were fitted to the double skin metal roof sections. Vertical ducts take the air to fabric ducts which then evenly distribute the air. Fabric ducts can provide draft free conditions.

The air change rate used in this fitness centre was 10 acphr in the general fitness areas and 12 acphr in the spinning area.
Sound attenuation has been incorporated into both the inlet and extract systems.

Horizontal nozzles are incorporated into the duct.This is to create an induction effect to distribute the air evenly between the ducts. If these are not used then the air can fall vertically and produce non-uniform cooling.