Condenser coils - a source of dirty energy

Now that I have your attention were you aware of the true cost (££££££££'s) of clogged fin coils on your cooling plant?

Outdoor condenser fans draw a large quantity of air and the flow through a 3 ton condenser coil is 2,400 Cubic Feet per Minute. (1.16m³/sec).

If you calculate the volume over a typical cooling season of 2000 hours, then this equates to 288 Million Cubic Feet (8million cubic metres).

Unfortunately, AC condenser coils have never been designed for the real world. As Jim Mazies, HVAC/R Building Engineer for the University of Chicago states:

“I’ve been in the HVACR business for over 40 years now and never understood why manufacturers of condenser coils for commercial a/c units can never build a coil that is made for planet Earth and not for outer space.  

Condenser coil fin spacing should be made just like they did on the older refrigeration units — anywhere between 8-12 fins per inch (FPI). 

 

Any more than this and servicemen have to lug either the power washer on roofs or lift the heavy, bulky tanks of CO2 just to clean these coils, only to hope that they will stay clean for the rest of the summer, with dirt and cottonwood only making things worse”.

To say it simply, “If you can’t see through the coils when they are clean, they shouldn’t be built”!

Unfortunately Jim, the only thing that drives coil design is maximum heat rejection efficiency under clean conditions. This means that you must create the greatest surface area to ensure maximum cooling and the only way to do that is to increase the FPI.

A manufacturer recently admitted that all cooling coils are specified with a built in factor for dirty fins.

According to EPA research, 0.042 inch (1.06mm) of dirt on an air conditioning coil can reduce its cooling efficiency by 21%.

Debris clogged condenser fins and dirty coils reduce air flow, and add more heat to the system causing the compressor to work harder with higher system temperature and pressure. 

Dirty coils reduce the AC system cooling capacity and increase electricity consumption. This means decreased equipment life with increased maintenance, repair and operating costs. Hence the slight play on words statement - Condenser coils - a source of dirty energy.

Preventing Equipment Damage is Easy!

The PreVent Air Filter Screen is designed to keep any outdoor air conditioning unit from clogging up with debris caused by construction dust, lint, insects, seeds, leaves or grass clippings that get could get sucked into the coil.

The screens are manufactured using:

BHA Media for anything over 1.5m wide & up to 6.3m long

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 Media for anything up to 1.5m wide & up to 6.3 long

Black Polypropylene HoneyComb Weave is a 3 Dimensional Polypropylene Honey Comb Weave which has a lower air flow resistance whilst 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

It is a simple and cost effective solution. 

Fit protective screening around your cooling coils and keep the contamination away from the fins. 

Remember the trade name for a genuine air intake screen product.