Air Cooling Units

[Samarjit Sen]

Generally for an air cooling unit for a low temperature application, using draw through fans are common. Can some one suggest as to what should be the Static Pressure of the fan for such units, when the fin spacing 3 mm ( 8 fpi) and a throw of 30 ft are required.

By stating low temperature application, I mean a Room Temperature or - 1 Deg C and down.

Thanks in advance.

With best wishes,

[US Iceman]

The coil static pressure loss is normally accounted for in the fan rating.

Typically when you are adding static pressure to unit coolers it is external to the fan/coil unit.

In your example, the standard fans should provide 30 feet (9.14 m) of air throw if it is a clear discharge with no obstructions.

[Samarjit Sen]

The fans shall be drawing the air through the finned coils and the discharge shall be free. In drawing the air there is bound to be a loss in the static pressure. If the velocity is not being maintained then the air throw will be less. To cover the air throw and the loss of pressure in drawing the air throgh the finned coil, there has to be a static pressure. All air cooling units depending on the size, fin spacing , air throw and the air velocity will be having fans and motors meeting the requirements.

I am sure that if references are made to the various Unit Cooler manufacturers, we can get the solution. As air circulation is very important in a Cold Room application, I thought I would be able to share the knowledge and information given by you all with the other engineers who are involved in such projects.