Corporate Buyers Guide

Liquid chillers have two cooling (chilling) loops. The main chilling loop is the one that goes from the chiller to the process or machine to be cooled, removes heat energy and then returns to the chiller.

When the hot fluid returns to the chiller, the second loop is needed to remove the heat extracted so the cooling fluid can be circulated again. The removal of the heat from the cooling fluid can be air blowing over finned coils containing the fluid or the finned coils can be submerged in a bed of water or other fluid transferring the heat.

The air cooled units are usually the small portable models with a heat removing capacity of ¼ ton to near 30 tons ( 1 ton heat capacity = 12,000 BTUs = 4 kw hrs). Water cooled are mostly the medium capacity, fixed mounted units of 30 to 100 tons. Above 100 tons come the large mostly cooling tower air and water cooled units. The small and many of the medium capacity liquid chillers can be purchased from catalog specifications. A word of caution for air cooled units: make sure that there is enough air space for the hot air to circulate away from the chiller to dissipate the heat. Many medium and all large units require manufacturers advice to specify and to install.

The cooling fluid (liquid) in the chiller is water and the heat removal capacity is based on water. However, for special applications chemicals such as glycol or 3M FCC may be added. This reduces the heat absorbing capacity of the water and the rating of the unit has to be reduced.

Portable dust collectors could be vacuum cleaners. But, for most industrial applications the air has to move at a greater volume with less noise. The industrial portable dust collector comes in two styles. The source point dust collector has one air input. It is also called a fume extractor because it is the preferred unit for soldering or welding work stations. It has a high air volume, but runs very quiet.

The standard portable dust collector has usually more than one air input. Each air intake is a large round opening to which a hose 12 feet long can be attached.  A 12 foot hose is standard on many models. Hose diameter varies from 4 to 9 inches.

The air capacity varies from 400 to 2600 cfm. The fan motor ranges from 1 to 5 hp and the filter size from 40 sq ft to 450 sq ft. The filter configuration may be cartridge or flat. The larger models usually are cartridge filters.