Specifications

The Purpose of an Air Dryer
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A Brief Physics Lesson.
Though not readily visible, water vapour is present in the atmosphere that we live in. When an Air Compressor is used
to increase the pressure of air from atmospheric to something higher, the increase in pressure tends to force the water
vapour to condense into water droplets. As there is a great deal of heat present in the compressing of the air, and the
warmer the air temperature the more moisture it can hold, the hotter compressed air leaves the Compressor Unit with
all the moisture present in a vapour state. In other words, the air has all the moisture in it still in vapour form, none of it
has changed to a liquid state.
As the compressed air travels through the compressed air system, and cools down to the ambient temperatures, the
water vapour held in the air begins to condense into liquid droplets inside the air lines. The temperature at which the
water vapour begins to form into liquid droplets is known as the ‘dew point’.
And What Will a Dryer do for Me ?
Air containing moisture may not be harmful to some industries, but it may be very harmful to others. Applications such
as the autobody refinish industry and HVAC installations are areas where moisture content is very critical, resulting in
inferior finishes or damaged controls and componentry.
With a Refrigerated Air Dryer, the compressed air is cooled down to a temperature at which the moisture content is
condensed into a liquid state. The Dryer then, by way of an internal Separator, discharges the liquid. The key to the
Refrigeration Unit is the ability to dry the air at a dew point temperature below the lowest temperature to which the
compressed air will be exposed.
With a properly sized and maintained Refrigerated Air Dryer, and coupled with suitable filtration, moisture at your point
of use will be non-existent.
How can I Justify the Expense ?
1. Tool maintenance will be reduced. Water, oil, and additional contaminants may cause tools to stick, jam, or clog.
2. Tool life will increase. Water washes away lubricants, causing excess wear and corrosion.
3. Air consumption will be reduced. More air is used when it contains water, oil, etc in order to blow out sludge. Also,
water will corrode the inside of the air lines.
4. Production will be increased. Workers can use their tools immediately, as there is no need to purge water or
contaminants from the air lines.
5. Piping life is extended indefinitely as internal water corrosion is eliminated.
6. Production quality is improved and maintained there. Instruments, etc are sensitive to water and contaminants.
Poor air quality may cause poor product quality, increased rejects, and production shut-downs because of
malfunctioning controls and tools.
7. Spray paint production is boosted. Water on or under the paint surface will cause both blisters and paint runs,
requiring both refinishing and repainting.
8. Trap maintenance down-stream of your Refrigerated Air Dryer is almost eliminated. The only maintenance
required regularly is at the Dryer Separator.
9. New installations will not require pitched air lines, drop legs, traps, or drains.
On-Site Electrics
Why do I need a Refrigerated Air Dryer ?
Refrigerated Air Dryers
Information Bulletin IFB-01
March ‘07
For Sales & Service contact:
CENTRAIR Air Systems & Supplies 705-722-5747 sales@centrair.ca www.centrair.ca