Desiccant dehumidifiers remove moisture from the air through adsorption. This is a process in which the molecules of a gas or liquid stick to the surface of a liquid or solid material. In contrast, refrigeration-based dehumidifiers use cold coils to condense warmer, humid air into water. Each of these processes is ideal in different conditions. Since a desiccant dehumidifier doesn’t use condensation, there are no risks of frost building up in low temperatures.
Various industries find applications for desiccant dehumidifiers due to their versatility. Some of these are in food and pharmaceutical production, refrigerated storage areas, drying new structures, or restoring water damaged spaces. Depending on its purpose, the size and capacity the business calls for, there are multiple options to choose from.
Our Top Picks for the Best Desiccant Dehumidifiers for Commercial Use
Capacity: 118 PPD
Current: 12 Amps
Voltage: 110-120 V
Dimensions: 33.13” H x 21.14” W x 20.25” D
Weight: 95 lbs.
Dri-Eaz is a brand well known in providing reliable, portable solutions to water damage restoration and maintenance. Among their line of commercial dehumidifiers is the Dritec 4000i Desiccant Dehumidifier. Unlike the larger refrigerant models from the company, the Dritec continues operation in subzero temperatures and lowers humidity down to 0% RH.
It is ideal for drying hardwood floors, plaster, bricks, and concrete. This versatile, portable dehumidifier removes up to 118 pints per day in AHAM conditions (80F, 60% RH). It moves the process air at 395 CFM and reactivation air at 65 CFM.
The digital display on this smart dehumidifier shows real-time temperature and relative humidity percentage readings for the inlet and outlet ducts and reactivation air, the average amount of moisture removed, and how many amps are currently being used. You can reset the job hours and set the humidity from 5% to 60% RH with the onboard humidistat. It also includes the four options for display language: English, French, German, and Spanish.
Similar to the refrigerant units from Dri-Eaz, the Dritec 4000i features large semi-pneumatic wheels and a foldable handle for easy storage and movement. It operates vertically and horizontally for flexible setup in low-clearance areas like crawl spaces. There are multiple ducting options based on your needs. The unit is equipped with a Positive Thermal Coefficient (PTC) heater for better efficiency, safety, and longer life.
Weighing 95 pounds, it’s about 33% smaller than the closest competitor. The onboard compartment provides storage for accessories and includes a manual for ducting. The rugged steel case is guaranteed with a 7-year warranty, two years for the desiccant rotor, and one year for parts and labor. For maximum dehumidification, it is recommended to operate in conjunction with a powerful refrigerant dehumidifier.
Capacity: 132 PPD
Current: 24 Amps
Voltage: 110-120 V
Dimensions: 36” H x 20” W x 20” D
Weight: 105 lbs.
Quest dehumidifiers offer powerful dehumidification in indoor growing facilities and other commercial areas. They come in a variety of designs and functions, from overhead dehumidifiers, portable models, to commercial desiccants. Their leading commercial desiccant unit, the Quest Dry 132D performs well from 10°F to 120°F. This unit removes up to 132 pints of moisture per day in AHAM conditions. A supply of warmer reactivation air increases performance in lower temperatures.
It can be installed vertically or horizontally with multiple ducting options. The process air enters through an 8-inch duct and moves at 385 CFM, while the reactivation air enters through a 6-inch duct and moves at 75 CFM. Ducting accessories as well as the remote humidistat must be purchased separately.
It comes with two filters to clean the air of pollen and dust – a MERV 11 filter for the process air, and a MERV 8 filter for the reactivation. This model is commonly used by indoor growers specifically during the flowering season. It is best used in combination with a high efficiency dehumidifier like the Quest Dual 155 Overhead Dehumidifier.
Capacity: 95 PPD
Current: 11.7 Amps
Voltage: 110-120 V
Dimensions: 13.6” H x 13.9” W x 24.8” D
Weight: 45.2 lbs.
The EPD200-PRO DryFan is a USA model of specialized boat dehumidifiers by Dutch company Ecor Pro. It has the highest capacity for moisture removal among the PRO line at 95 PPD, making it the smallest and most lightweight dehumidifier at this capacity.
It operates from -4°F to 104°F with maximum airflow of 309 CFM. Using the four-hole system, the two air streams with two internal fans are completely separate. The second fan allows for pressure-neutral drying wherein only the processed, dry air comes into the room and all moisture is vented outside. This makes the EPD-200 PRO the perfect dehumidifier for large, sealed, cold areas like freezers.
Built with 316 marine grade stainless steel, it is highly resistant to salt air and other harsh environments. It is ideal for sea vessels, boats, yachts, and other maritime applications. It is also suited to food storage and preparation, catering, and hygienic areas. The small casing can be mounted in any orientation, on the floor, wall, or ceiling. It comes with a dust filter that can easily be shaken clean or replaced.
Given its compact design, one person can carry the unit from one job site to another with its carrying handles. It self-regulates to ensure efficiency at any temperature and humidity level. It also features auto restart in the event of a power interruption. There is an option to connect the Ecor Pro EPHUM220 humidistat for remote operation and control.
Capacity: 118 PPD
Current: 31 or 15 Amps
Voltage: 220 or 460 V
Dimensions: 56” H x 28” W x 23” D
Weight: 200 lbs.
Ebac features a range of high capacity commercial dehumidifiers for crawl spaces, factories, warehouses, and other industries. The most powerful unit in its DD series of desiccant industrial dehumidifiers is the DD1200 with a capacity of 562 pints on high extraction settings. It remains efficient in low temperatures down to -4°F.
This Ebac industrial dehumidifier has an airflow rate of 883 CFM for the process air and 195 CFM for the reactivation air. You can select from three drying modes: high-efficiency drying, deep drying, or high extraction. The unit has a moisture removal rate of 402 PPD on high-efficiency setting, and 508 PPD on deep drying.
This commercial unit features easy-to-use electronic controls as well as an hours run meter to track job hours and an ammeter to monitor drying effectiveness. It shuts off automatically when the temperature reaches 104°F. You can choose between Auto or Manual mode of operation, and ten fan speeds. There is also an option to connect a remote humidistat for auto operation and control. The unit must be ducted on both the process air and reactivation air outlets.
The DD1200 is available in two voltages, 220 and 460. It comes with two inlet filters to help clean the air that enters. The PTC heater ensures maximum drying is quickly reached and maintained throughout operation. Like other models from the DD range, it incorporates a patented PPS rotor with 82% active silica gel. Its rugged design with a stainless steel case is built for efficiency and long life. Some common applications of this model are in warehouses, factories, hotels, pharmaceutical and food industries.
Capacity: 570 PPD
Current: 23 Amps
Voltage: 480 V
Dimensions: 52” H x 30” W x 53” D
Weight: 510 lbs.
Quest partners with Trotec from Germany to introduce the TR line of desiccant dehumidifiers for cold chain industries. One of their mid-sized models is the TR 570 with a water removal rate of 570 pints per day. With its ability to operate from -4°F to 104°F, it is ideal for food production, nutraceutical and pharmaceutical facilities, refrigerated storage areas, or any industry in need of constant humidity control at low dew points.
The process air stream flows at a maximum of 1380 CFM and the reactivation air stream at 220 CFM. During operation, the process air goes in through one fan and out through the dry air outlet. The regeneration air is pulled in with its own fan and through the purging sector for heat recovery and cooling, which reduces energy input and improves performance. The fan speeds are also adjustable.
The device may be installed inside or outside the room with options to duct the reactivation air inlet from and out into the outside, or duct the process air inlet from and out into the room for a pressure-neutral drying. It may also be installed outside the conditioned space for positive pressure. Depending on the application, coarse or fine filters are located in each air inlet. Quest Trotec models are designed with modularity, which means you can bring them with you through every development in your business without needing to install new units – simply upgrade or replace some parts of your TR 570.
What to Consider Before Buying a Desiccant Commercial Dehumidifier
Desiccant commercial dehumidifiers are useful in almost any industry. When choosing the right dehumidifier for your business, there are a few considerations you must take first.
This refers to the physical dimensions of both the dehumidifier and the area you need to dehumidify. Desiccant dehumidifiers generally come with a compact build for simple to heavy dehumidification tasks in small areas. They do not need a tank or pump, which both add bulk and inconvenience to refrigerant dehumidifiers. However, commercial desiccant models do need to be ducted outside or between floor joists, depending on the job.
Even the best commercial dehumidifiers perform better in temperatures above 60°F. Although some portable dehumidifiers are designed to work down to 41°F. Desiccant commercial dehumidifiers are ideal for moisture removal in low temperatures that refrigerant models cannot handle.
Commercial grade desiccant units remain efficient even down to subzero temperatures. This makes them the best dehumidifiers for places with extreme temperatures and businesses in constant need of humidity control in cold storage areas.
Make sure that the dehumidifier you use can operate effectively at the temperature you need. Most models will simply shut down if temperatures go beyond their capabilities.
Any type of dehumidifier removes more moisture at a higher humidity level, but some remain more efficient even at the lowest settings. Most consumer grade dehumidifiers can lower the humidity down to 30%. Desiccant commercial dehumidifiers can go way below the ideal range of 30-50% for the average person – even as low as 0% RH.
As you may know, organic products like fruits and vegetables thrive in different levels of humidity. The common belief is that fruits need low humidity and vegetables need high humidity. Storage areas need to be kept at the right humidity level to maintain the freshness of the products. Other perishable foods or consumables must be stored properly.
Extremely low humidity levels may also be needed to remove any and all moisture from materials that are very difficult to dry. This includes construction materials, structures, and water restoration sites.
Desiccant dehumidifiers in general are more economical than refrigerant dehumidifiers. Since desiccant models work in a wider range of temperatures and humidity levels, they use energy more efficiently. Obviously, a larger size and higher capacity unit would require more power to operate. For reference, the smallest models we featured operate with at least 1000 Watts. Power consumption ultimately depends on the size, capacity, and other specifications. Before installing a dehumidifier or purchasing a portable model for your business, it is important to consider your budget.
Commercial dehumidifiers sometimes allow multiple ducting options. This can help save space in the room during operation. Ducting also lets you reach small or tight places like a crawl space or basement that may be hard to reach for larger models. You may duct through a wall from the outside to supply fresh air into the room or multiple rooms. You may also operate the dehumidifier outside the room and duct the process air inlet from the room and out into the room for pressure-neutral drying. Study the space you need to dehumidify in order to find the best choice for you.
How Does a Commercial Desiccant Dehumidifier Work?
Before we dive into the process by which a commercial-grade desiccant dehumidifier lowers humidity in the air, let us look at the different components usually found in a desiccant dehumidification system.
A desiccant dehumidifier will not be called so without the desiccant itself. It is a hygroscopic material, typically silica gel, that removes moisture from the air through adsorption and releases it when heated. The desiccant is infused into a corrugated wheel called the desiccant rotor. Powered by a drive motor, the wheel rotates slowly though two air streams.
A fan or several fans pull air into the system and exhaust processed air. A heater warms the reactivation air to dry the desiccant. Like most other dehumidifiers, filters protect the machine from unwanted particles in the air. These are the main components of a desiccant type commercial dehumidifier. Larger models may include additional filters and cooling coils.
The process air, or the humid air from the room, is drawn into the dehumidifier and passes through the process zone of the desiccant rotor. This section makes up at least 50% up to 75% of the rotor. The desiccant adsorbs moisture from the air. Depending on the ambient temperature and dew point, the air may leave the dehumidifier warmer or cooler. If necessary, some units include an outlet filter to further clean the air or cooling coils to lower its temperature before being reintroduced to the room environment.
The second air stream passes through the remaining part of the rotor, the reactivation zone, in the opposite direction of the process air. The heater warms the reactivation air, producing hot, dryer air. In most models, this heater is a separate component in the system. While in some, the air is warmed through the recovery of heat energy dissipated by the rotor. In this case, the desiccant wheel is also called a thermal wheel. This process of heat recovery makes for a highly energy efficient device.
When the reactivation air passes through the wheel, moisture is transferred from the desiccant to the air, effectively “reactivating” the desiccant. The now humid air from the reactivation zone is released from the dehumidifier into the outside. This cycle repeats and the desiccant rotor makes at least two revolutions per hour, depending on its size and operation. The process air and reactivation air pass through the desiccant continuously and simultaneously in separate air streams. See the figure below for a diagram of a desiccant wheel operation.
How Does a Desiccant Commercial Dehumidifier Compare to Other Models?
There are different types of desiccant dehumidifiers depending on your need for moisture removal. They work by the same principle – a desiccant material absorbs or adsorbs the moisture from the air.
Types of Desiccant Dehumidifiers
- Disposable Desiccant Dehumidifier
Also called moisture absorbers, this type of desiccant dehumidifier contains crystal-like substances that absorb moisture, like silica gel. They are small and cheap and have very low dehumidifying capacity. They do not need to be plugged in order to start working. Moisture absorbers are ideal for wardrobes, cabinets, or small rooms with little moisture content. They must be disposed of after one use.
- Renewable Desiccant Dehumidifier
Another type of portable desiccant dehumidifier called the renewable desiccant dehumidifier contains silica gel which removes moisture from the air by adsorption. They are similar to the disposable desiccant in size, capacity, and price. They also do not need to be plugged, making them the best desiccant dehumidifier for wardrobes, kitchen cabinets, and gun safes without sockets. They do need to be recharged every few weeks by plugging or heating in an oven to dry out the moisture.
- Full Size Desiccant Dehumidifier
A full size consumer grade desiccant dehumidifier works in a similar process as the commercial type that is the main topic of this article. The difference is condensation occurs after the reactivation air removes the moisture from the desiccant. Typically made of plastic, the condenser turns the warm moist air into water droplets collected in a tank or drained out of the dehumidifier. This type of desiccant dehumidifier is similar to the standard compressor dehumidifiers in terms of size and capacity.
- Commercial Desiccant Dehumidifier
These are commonly used in commercial spaces with low temperatures and low humidity levels or in drying materials that are difficult to dry. They come in a variety of sizes, from a compact, portable model that can be rented for construction sites or water restoration jobs, to a complex structure installed into a commercial building as part of its HVAC system. They are the best commercial dehumidifiers for colder temperatures or lower humidity levels.
Advantages of a Commercial Desiccant Dehumidifier
Operates at Lower Temperatures
The main difference between a desiccant dehumidifier and a refrigerant is the method of moisture removal. Refrigerants use cold coils to cool the moist air until it reaches 100% relative humidity and the moisture condenses into water. The moisture accumulated is pumped out or collected in a tank while cool dry air is released to the room. This method works best in highly humid, warm climates.
Standard refrigerant type dehumidifiers can only operate in temperatures as low as 41F and their efficiency starts to decrease at 55F. This is because the already cold air cannot be further cooled by the coils. To avoid frost buildup, some refrigerant dehumidifiers feature auto defrost that automatically stops operation to defrost.
On the other hand, a desiccant commercial dehumidifier uses a process called adsorption instead of condensation, as we have discussed in the previous section. Since it doesn’t use refrigerant coils, it doesn’t need to cool the ambient air and continues to operate in lower temperatures. And because moisture never condenses into water and the system constantly uses heat, there is no condensate that can form ice, cause a blockage, or damage the internal components of the machine.
Operates at Lower Humidity Levels
Although commercial refrigerant dehumidifiers use different technologies to enable low temperature operation, there is a limit to their capabilities both in low temperatures and low humidity levels. Most models can lower humidity down to 30% – anything below can be considered harmful to breathe. This makes them great for residential areas and commercial spaces frequently populated by people.
For industrial spaces that need extremely low humidity, the standard dehumidifier needs to work extra harder. This is because it removes moisture by cooling the humid air just enough to reach the dew point where the water vapor condenses. In turn, already dry air needs to be cooled even more in order to reach that point.
A commercial desiccant dehumidifier is specially useful in an environment with extremely low temperature and humidity. It is effective in making already low humidity levels even lower. Regardless of the humidity level, the desiccant is a highly adsorbent substance that will keep taking moisture until it is fully saturated. This never happens because the reactivation process constantly dries the moisture out of the desiccant at the same time.
The dehumidification process inside a desiccant dehumidifier does not limit its dehumidifying capacity. Since a desiccant dehumidifier can handle extremely low temperatures and humidity levels, it operates with the same efficiency in any kind of environment. It can remove just as much moisture in an environment at 90°F, 90% RH, as it can in a 60°F, 40% RH.
The average commercial refrigerant dehumidifier can remove a maximum of 190 pints of moisture a day in a room at 90°F, 90% RH. But in an average condition of 80°F, 60% RH, its capacity lowers significantly at 85 pints per day. At an even lower humidity level, say 40%, it can take about 25 pints of moisture per day. The same applies to a consumer grade refrigerant dehumidifier.
A desiccant dehumidifier is also more compact and lighter. A compressor-based dehumidifier is composed of heavy metal parts, an evaporator and a condenser. The main bulk of a desiccant dehumidifier is in the desiccant wheel. Since it doesn’t produce water at any stage, it doesn’t need a tank or a drain hose.
Who Needs Commercial Desiccant Dehumidifiers?
Because of its versatility, efficiency, and the ability to operate at extreme temperatures, commercial desiccant dehumidifiers have many applications in various industries. Some of these are the following.
- Food items are sometimes processed, preserved, and packaged at very high temperatures. This can lead to excess moisture, which can affect the shelf life and safety of the products. Maintaining the right temperature and humidity throughout production is absolutely essential.
- Similar to food production, pharmaceutical production also demands for strict control of the environment. The presence or absence of moisture may be detrimental to the manufacture of a certain drug. For example, the process of compressing powdered substances into a tablet requires an extremely dry state. Otherwise, moisture may change the composition of the chemicals.
- Warehouses and storage facilities may be susceptible to mold growth, rust, and corrosion if humidity is not controlled. Stored goods may also be damaged by excess moisture. They need constant, efficient dehumidification at whatever temperature and relative humidity level are most ideal.
- Commercial dehumidifiers may also be needed in equipment storage rooms. Controlled temperature and humidity is essential to assure proper function of electrical and mechanical equipment.
- In drying materials that may otherwise be really difficult to dry, a commercial desiccant dehumidifier may be the solution. It can be used in drying a variety of products, from processing to packaging stage. It can also be used in drying new constructions and water damaged sites. Hardwood floors, walls, basements, or crawl spaces that refrigerant models cannot handle might need a desiccant dehumidifier.
- You can find a desiccant dehumidifier useful in other commercial spaces where excess moisture may pose an issue. These include but are not limited to: pools, spas, greenhouses, supermarkets, ice arenas. Storage areas for frozen products also make use of desiccant dehumidification.
Proper Usage, Maintenance, and Storage of Commercial Desiccant Dehumidifiers
Different models are designed for different operations, but there are some common practices you must observe to ensure the efficiency and longevity of the product. From installation to operation, follow the instructions in the manual. Be reminded of the temperature ranges deemed safe for operation. For your safety, it’s best to let a professional do their job. Although some portable models, like the Dri-Eaz Dritec 4000i, are simple enough to operate even in residential areas.
During maintenance, make sure the unit is turned off and unplugged before removing or cleaning any parts. It is important to regularly inspect the filters for dust or dirt. Wash or replace them as needed. The desiccant rotor must also be cleaned, or cleared of dust and debris depending on each unit’s requirements. Vacuum the interior as necessary. Due to the nature of the dehumidification process, most desiccant dehumidifiers actually require very little maintenance.
Is a desiccant dehumidifier better?
It depends on the purpose. Desiccant dehumidifiers can operate in extreme temperatures and humidity levels. For this reason, they are most useful for spaces that need dehumidifying at temperatures as low as 0F or humidity as low as 0% RH.
How long do commercial dehumidifiers last?
Commercial units are built with more durability than consumer grade models. A good commercial dehumidifier should last at least five years, depending on the unit and brand, and the care and maintenance.
How much does a commercial desiccant dehumidifier cost?
Commercial desiccant dehumidifiers range from portable models to a whole dehumidification system installed into a commercial building. Costs depend on the purpose, size, and capacity. As of writing, the smallest unit we featured cost at least $3,000. Mid-size units can go up to $12,000 or higher.