We all know and understand the importance of planned preventative maintenance on refrigeration systems. We help our customers to understand how this benefits plant performance and longevity both in the short and long term. However, one area that can be overlooked is the regular cleaning of coolers and associated drains.
With the summer weather, and in particular the recent and unbroken spell of hot weather, a number of companies will be experiencing the problems of maintaining required temperatures in both chilled and freezer environments. When this happens, thoughts can often focus on what small changes can be made to prevent this in the future. One question should be “are the evaporators/coolers clean and working efficiently?” A second should be “have the condensate lines been thoroughly cleansed and voiding the water when they are being defrosted”?
How does dirt build up in coolers?
Because the coolers are effectively recycling the air in the chamber, they become a focal point for the build-up of dirt and general detritus. Heavy use of cardboard, wooden pallets and plastic means dust and plastic strips are drawn into the fins or air diffusers. When the air-flow is insufficient to redistribute the chilled air back into the chamber the entire system has to work harder to maintain temperature.
Similarly, when drain-lines are not kept thoroughly clean, a build-up of biological slime often ends up breaking off and moving down the line on the next defrost. Pipe-fitters, being tidy workers, tend to follow the exterior wall and at every buttress it is not unusual to have a series of right-angle bends. It only takes one large lump of biological slime to end up in this area and the flow is stopped. The water then backs up into the drip-tray of the nearest cooler. When the fans are switched back on, after the defrost, the contaminated water is drawn out of the drip-trays and broadcast over the product below. At this stage it is not only water that hits the fan!
Is regular cleaning cost effective?
Many companies have their coolers cleaned twice a year as they understand that effective refrigeration requires effective cleaning.
An experiment carried out by Distribution Hygiene Services, together with a leading food distributer, aimed to evaluate whether cooler cleaning is cost effective. The results proved beyond doubt that investing in keeping equipment clean pays for itself and offers savings straight away. Two weeks prior to the clean taking place the electricity usage on four coolers was measured by the senior engineer. On the day of the clean an airflow reading was taken before the work was carried out. It was noted that the coolers were not particularly dirty, but after a full clean was carried out an airflow reading was taken again and showed a marked increase. The increase in airflow averaged at 12% (it is not unusual to see increases in excess of 50%). The coolers were clamped again to measure and record the energy usage. The results showed an energy saving of 21% which equates to a saving of £1,400 in energy saving per cooler per annum. This proved beyond doubt that even slightly dirty coolers cost more to run and, under clean conditions, huge savings can be made.
As well as the proven cost savings on energy usage there are a number of other benefits from keeping coolers in a clean and tidy condition. In chambers where coolers have been properly cleaned the air quality is much improved, which is often commented on by the workforce. There is also the improved health and safety element of a clean. Hertford University has analysed the sludge that has been removed from cooler drain-lines and, whilst biological slime is not itself injurious to the human condition, it is a perfect environment for other pathogens to thrive.
So the old saying ‘cleanliness is next to godliness’ is definitely true as far as ensuring that your refrigeration plant is truly effective when you most need it.
Find out more
Distribution Hygiene Services is a specialist in providing professional industrial cleaning service. So if you are looking for a company to help improve cooler performance without disrupting your business, please contact
[email protected] or 01763 287267.
For all your refrigeration project and maintenance requirements please contact
[email protected] or 01279 408690.