Time for a change in 2014 - Air Intake Filter Screens

A major manufacturer recently admitted that all cooling coils are designed with a % factor for inefficiency caused by dirty fins.

Another confirmed that in the UK, the installation of an air intake filter screen would be more beneficial to equipment efficiency than the possible marginal loss of air flow.

It is not surprising when you consider that 0.042 inch (1.06mm) of dirt on an air conditioning coil can reduce its cooling efficiency by 21%. The highest resistance at 3.05m/s is only 22.42 pascals and yet the air intake screen will largely prevent airborne debris from impacting the coil.

Debris clogged condenser fins and dirty coils will reduce air flow. This will add heat to the system and cause the compressor to work harder with higher system temperature and pressure.

A dirty coil will reduce the AC system capacity to cool and demand greater airflow which will increase electricity consumption.

The result is decreased equipment life, increased maintenance, repair and operating costs.

But it is not just cooling coils that can benefit. If you use an air intake screen instead of standard pre-filter media you will get increased airflow, increased debris collection and reduced maintenance and running cost. 

PreVenting Equipment Damage is Easy!

The PreVent Air Intake Filter Screen is designed to keep any outdoor air movement plant from clogging up with construction dust, lint, insects, seeds, leaves or even grass clippings that might get sucked into your equipment or filter system.

Air intake screens are manufactured using two types of filtration media:

BHA - Black Pvc Coated High Abrasion Media is a 9x9 1000 Denier Multi Polymer Coated Polyester Mesh.

The air flow resistance of a clean fabric single layer is as follows:

0.50m/s 1.25pa
2.03m/s 8.75pa
3.05m/s 17.pa

BHC - Black Polypropylene HoneyComb Weave is a 3 Dimensional Polypropylene Honey Comb Weave with a low air flow resistance and the electrostatic charge attracts dust from the air.

The air flow resistance of a clean fabric single layer is as follows:

0.50m/s 1.25pa
2.03m/s 12.45pa
3.05m/s 22.42pa

 Air intake filter screens are a simple solution to a difficult and time consuming problem:

• Air intake screens are easy to fit to any plant or equipment with air movement. 

• The filter screen keeps debris on the outside and can be easily cleaned with a vacuum cleaner, hosepipe or brush.

• They can be fitted by your own maintenance teams or RAB can fit them for you.

• Fixings include grommet and self tappers, quick release fasteners, Stayput Fasteners™  aluminium, stainless or galvanised steel frames, magnetic framework, velcro and many more. 

• RAB air intake screens are manufactured to your specific requirements. They can be supplied with any combination of fixings or made to any shape required by your particular application. 

• Air intake screens have so far been fitted to chillers, dry air coolers, VAV and VRV units, split condensers, air handling units and cooling towers.
  
  
  
  
   
  For more information
  
  
   
  
  
  http://www.rabse.com/wrap-around-filter-screens
  
  
  
  
  
   
  Stayput Fasteners Website
  
  
   

Retail refrigeration

The cost of refrigeration energy has been estimated at some 500 million per year and in the food, drink, supermarket and cold storage sectors this will account for a significant proportion of the site energy costs (ctg046_refrigeration_systems).

This Carbon Trust report dated July 2011 estimated that refrigerated display cabinets use a minimum of 5,800GWh per year. As a GWh is 1 million KWh then the cost of this energy at current values will exceed £754m per annum and is a significant drain on the UK resources.

There are a number of ways in which this energy can be reduced but the most effective is regular cleaning and maintenance which (according to the Carbon Trust) would save up to 10% of the consumed energy.

In the paper “ENERGY CONSUMPTION AND CONSERVATION IN FOOD RETAILING” published by the Brunel University the author states “The energy consumption of supermarkets will depend on business practices, store format, product mix, shopping activity and the equipment used for in-store food preparation, preservation and display. The electrical energy consumption can vary widely from around 700 kWh/m² sales area in hypermarkets to over 2000 kWh/m² sales area in convenience stores. The refrigeration systems account for between 30% and 60% of the electricity used”.

Based upon a unit cost of 0.10 per kWh and taking 30% as the total cost of the refrigeration system then each m² will cost 21.00 per hour. The enormous amount of electricity required for supermarkets to run refrigeration units makes up around 40-70% of their total energy expenditure, depending on store size. It is also estimated that there are approximately 0.8 million refrigerated display cabinets in the UK.

Additionally a typical condenser will cost between £100 and 500.00 to clean and this essential task must be completed to maintain compressor efficiency and reduce failures. 

Clogged condenser coil. Only 1mm of dirt will cause a 21% drop in efficiency.

In the Carbon Trust report the following message is regularly highlighted:

Good practice inspections and maintenance saves energy and money

• Look out for debris/dirt build-up on the Condenser.
• Regularly clean condensers and evaporators.
• Cleaning a blocked condenser will improve compressor efficiency.
• Find out where your condensers are, and check them out.
• If they’re dirty or blocked with debris, they’re costing you money.
• Make sure the cleaning process doesn’t just push the dirt deeper between the fins.

And now there is a simple way to maintain clean condensers which does not involve a specialist technician and keeps the dirt from the fins.

An air intake filter screen is designed to maintain airflow (resistance 1.25pa @ 0.50m/s) whilst filtering out the dirt and debris that is drawn into a refrigerated cabinet enclosure.

This means that you can easily see any dirt build up and quickly remove it by washing or vacuuming.

The patented Permatron PreVent® screen is supplied with a magnetic frame so that they can be easily simply removed when cleaning is required. For the Starbucks case history please check out the RAB website www.rabse.com.

Air intake screens are simple, innovative and hugely effective as they cut down the cost of maintenance whilst keeping coils free of debris.

If you could save 10% of your energy bill by spending a little would you give it a try?