Desiccant dehumidifiers have been around for a long time, despite their negative suffix. (I was always taught to never say “Can’t”.) They have applications in frozen food production, corrosion protection, ice rinks, plastic production and more. Even the little silica gel packages often found in medicine bottles are part of the desiccant family.

But these units have become very important tools for disaster restoration contractors. They differ from LGRs in how they remove water and the way they produce extremely dry air. In fact, you can actually overdry with desiccants.

Desiccant Performance Tips

If you already possess a desiccant dehu, this is nothing new. But experts say that many owners of these units may not be using them to their full potential. So if you’re looking to get the most out of your desiccant I have some suggestions.

1. Keep your duct lengths as short as possible and
eliminate sharp bends to have unrestricted airflow
and higher performance.
2. Long runs can also cause the reactivation air to
cool below dew point and fill the duct with water,
damaging the dehumidifier and the structure being
dried. While insulation will help prevent this, an
additional protection would be to have the ducting
slope away from the dehumidifier or a small drain
hole drilled at a duct low point.
3. Assist the processed air to travel throughout the
structure by using air movers.
4. Keep the ends of the process-in and process-out
ducting away from each other so as not to
adversely affect the unit’s efficiency.
5. Cold air is usually drier, so duct the process air inlet
from the coolest, driest air accessible, whether from
outside, an air conditioner or from an unaffected
area. (Also, since the rotor is highly heated to
release moisture it’s absorbed, the cool air coming
in will return it to an operable temperature.)
6. If the unit is far away from a window or door, then
duct the reactivated air into a high airflow LGR
dehumidifier.

While the majority of your dehumidifiers are usually LGRs, desiccants afford unique performance features that make them better suited to some specific drying applications. And since desiccants can also be a large investment, be sure you get the most out of them as you CAN.