Industrial Dehumidifiers

Guide to Choosing a Commercial Dehumidifier 

With the vast range of commercial dehumidifiers on the market, choosing the right one for your business is often a long process. 

Excess moisture is a problem for many organisations and solutions will differ from one business to another. For example, battery manufacturing facilities often need extremely low humidity levels of less than 1% RH, while other applications may need conditions of 40-60% RH to ensure that a process is within a pre specified humidity set point. Facility conditions, industry, function, and budget are some of the factors that can add to the complexity of selecting a suitable unit/s. Dehumidifiers can also be retrofitted to a facility, often to solve an existing problem in a facility. 

In this guide, we will discuss: 

• The different types of dehumidifiers commonly used in commercial and industrial premises 

• Dehumidifier applications 

• Factors to consider when sizing for a commercial dehumidifier 

What is a Commercial or Industrial Dehumidifier? 

Commercial dehumidifiers have been designed to remove moisture from large commercial or industrial spaces for long periods of time and are more robust than domestic dehumidifiers. Although they may function similarly to domestic dehumidifiers, the capacity, longevity, and performance are entirely different. Smaller domestic dehumidifiers, often seen in search engine results, are perfectly suitable for removing moisture in homes and small spaces but have limited use in a commercial setting. 

Types of Commercial Dehumidifiers 

There are two main types of commercial dehumidifiers: 

Refrigerant (condensing) dehumidifiers use a cold coil as part of the dehumidification process and are very effective in warm, humid areas. These units bring in air from the space and pass it over a cold coil which causes the water in the air to condense on the coil and is therefore removed from the air. This dry air is then put back into the space, lowering the in-room humidity. They are excellent for removing high levels of moisture, and can be very energy efficient, however, refrigerant units work best in temperatures above 15C and over 50% relative humidity.  

Desiccant (adsorption) dehumidifiers contain adsorbent material (silica gel) that removes moisture from the air chemically. Desiccant units do not need warm temperatures to operate, unlike refrigerant units. They can work in both warm and cold environments, which is why they are an excellent solution for cold rooms and areas where there is no heating. If your room needs to be kept at below 50% relative humidity, selecting a dessicant unit is essential as a refrigerant based system will struggle to reach this set point, regardless of temperature.  

For more information on refrigerant and desiccant dehumidifiers, see our in-depth article here on industrial dehumidifier technology. 

Dehumidifier Applications 

Cold Stores 

Humid air entering cold stores through doorways can increase humidity levels, increasing the likelihood of condensation forming. Too much moisture can lead to damaged products, compromised packaging, mould growth, and potential slipping hazards for employees. Although air conditioning systems inside cold room AHU systems can remove moisture to some degree, it can sometimes not be enough to prevent these issues. This is where desiccant dehumidifiers can work well as they can remove moisture in very low temperatures, down to well below freezing if needed. 

Swimming Pools and Spas 

The warm humid environment of spas and swimming pools make it the perfect breeding ground for bacteria and mould growth due to high humidity and condensation building up on surfaces. Not only does this affect the health and wellbeing of visitors but it can also increase the frequency and cost of maintenance. A refrigerant dehumidifier is best suited for swimming pool and spa dehumidification, due to the higher temperature and moisture levels present in this type of environment, which can often reach higher than 90% RH. 

Classic Car Storage 

Classic cars are extremely prone to the effects of fluctuating humidity and temperature levels in warehouses and garages; and long-term storage in these conditions can cause serious corrosion of iron car parts. The initial reaction would be to heat the storage space, which can reduce the humidity during the colder months. But this often results in high energy costs (often up to 10x more than a dessicant dehumidifier), and it does not address the humidity levels during the summer months. Heating a space also does not remove moisture, instead warming the air to reduce the relative humidity as a be product of the heating. This approach is also not controllable so you will not have control of the humidity in the space, which is critical in this application. The combat this problem, a desiccant dehumidifier is recommended to operate year-round and in all weather conditions. 

For more examples of humidity control use cases, see the industries section or the knowledge hub on our website where you can find additional case studies and information. 

Sizing a Commercial Dehumidifier 

This is not an exhaustive list and will vary depending on the industry and specifications, but some important points to consider when sizing for a commercial dehumidifier include:  

• The type of dehumidifier i.e. refrigerant or desiccant 

• The size of the facility or dimensions of the area/location 

• Room temperature and dew point 

• The target relative humidity 

• Conditions of the location and existing equipment 

• Energy usage and requirements 

• Internal moisture and people load 

• Doors and windows 

• Installation location i.e. in-duct, wall mounted, ceiling mounted, free-standing etc. 

Are you looking for more advice on industrial dehumidification systems? Then call one of our humidity control experts today on 01372 571 200 or send us a message using our contact form.