In high-temperature industrial environments such as drying rooms, heat treatment workshops, or enclosed factories during 

summer, excessive humidity not only impacts production efficiency and compromises product quality but may also accelerate 

equipment corrosion and even pose safety hazards. Therefore, choosing an appropriate industrial dehumidifier is crucial. 

This article provides a practical selection guide to help you make informed decisions based on the characteristics of 

high-temperature environments, avoiding common pitfalls.

Step 1: Define Core Requirements—Quantify Your Dehumidification Goals

The first step in selection is clearly defining your needs, which directly determines the subsequent technical approach 

and equipment specifications. You need to gather the following key parameters:

• Basic Space Parameters: Accurately measure the area (m²) and ceiling height (m) of the space requiring dehumidification.

  Multiply these to obtain the volume (m³), which forms the basis for calculating the dehumidification load. Some selection

  guidelines suggest a preliminary estimate of 1 liter/day of dehumidification capacity per 2.5 cubic meters of space.

• Environmental Conditions: Identify the operating temperature range and initial humidity level. High-temperature workshops

  or drying rooms may exceed ambient temperatures, necessitating high-temperature-resistant models. Additionally, determine

  the target humidity level (e.g., reducing from 70-90% to below 50%). The difference between initial and target humidity

  (humidity differential △) is a core variable for calculating required dehumidification capacity.

• Moisture Sources: Assess moisture generation within the workshop, including evaporation from processes (e.g., water vapor

  released during material drying), personnel activities, and equipment operation. This “wet load” must be included in the total

  dehumidification requirement.

• Fresh Air and Sealing: Inspect the space's airtightness. Continuous fresh air supply introduces humid external air, significantly

  increasing dehumidification burden. Ideally, the dehumidification space should maintain excellent sealing.

Step 2: Selecting the Technical Approach—Two Mainstream Solutions for High-Temperature Environments

For high-temperature, high-humidity environments, two primary technical approaches for dehumidification equipment are 

available, each with distinct principles and applicable scenarios.

• Solution 1: High-Temperature Resistant Refrigerant Dehumidifiers

This is the most common and economical dehumidification method. It operates by using a compressor to cool the evaporator 

surface below the air's dew point, causing moisture to condense and be removed.

High-Temperature Adaptability: Standard refrigerant dehumidifiers typically operate within 5-38°C (41-98°F). For high-temperature 

workshops, specially engineered high-temperature models are required. These incorporate heat-resistant compressors and specialized 

refrigeration systems, enabling operation in environments up to 20-70°C (68-158°F). This makes them a popular choice for many 

conventional high-temperature drying rooms.

Advantages and Limitations: Their strengths lie in high airflow handling capacity, efficient dehumidification, and relatively low 

acquisition and operating costs. However, their dehumidification capability is significantly affected by temperature. Evaporators 

are prone to frosting at low temperatures, while efficiency may decline in extremely high-temperature environments. More critically, 

air treated solely by refrigeration has a relatively high dew point, making it difficult to meet processes demanding extremely low 

humidity (e.g., dew points below 5°C or relative humidity below 40% RH).

• Solution 2: Desiccant (Rotary Wheel) Dehumidifier

Rotary wheel dehumidifiers employ physical adsorption principles, utilizing moisture-absorbing wheels (e.g., silica gel, molecular 

sieves) to directly adsorb airborne moisture. The wheel is then regenerated using hot air, enabling continuous dehumidification.

Exceptional High-Temperature/High-Humidity Adaptability: This is its greatest advantage in demanding environments. Desiccant 

dehumidifiers can process inlet air across a wide range of temperatures (-20°C to 50°C or wider) and relative humidity (1% to 100%), 

with virtually no environmental temperature limitations. For ultra-high-temperature applications or processes requiring both low 

temperature and low humidity, it is the undisputed preferred solution.

Deep Dehumidification Capability: Desiccant dehumidification effortlessly lowers air dew points below 0°C, achieving ultra-low 

dew points as low as -70°C—a feat unattainable by refrigeration methods. Consequently, it is widely adopted in industries demanding 

extreme dryness, such as lithium battery manufacturing, high-end pharmaceuticals, and precision electronics.

Energy consumption characteristics: Its core energy consumption lies in the thermal energy required for regenerating the desiccant. 

This thermal energy can be supplied by electric heating or inexpensive heat sources like steam or direct natural gas combustion. 

In factories with steam availability, energy savings are particularly significant. Analysis indicates that in HVAC systems, a combined 

desiccant and refrigeration solution can reduce total electricity consumption by 20-30% compared to refrigeration-only dehumidification.

Step 3: Comprehensive Decision-Making and Selection Criteria

After defining requirements and technical approaches, the following factors must be considered for final selection:

Energy Efficiency & Standards: Focus on the product's energy efficiency ratio (EER). China's T/CAS 436-2020 standard for industrial 

and similar-use dehumidifiers has significantly raised energy efficiency thresholds and provides testing methods for high-temperature, 

low-temperature, and other operating conditions, offering effective guidance for selecting energy-efficient products.

Control and Intelligence: Opt for equipment with intelligent precision control capabilities. Microcomputer control systems automatically 

sense humidity, enabling 1% accuracy settings and 24/7 automated operation to maintain stable humidity within the target range.

Equipment Reliability and Maintenance: High-temperature environments test equipment durability. Verify if products feature specialized 

designs for corrosion resistance and dust protection. Additionally, consider maintenance convenience—such as easy-to-clean filters and 

clear fault indicators—to reduce long-term maintenance costs.

Installation and Layout: Dehumidification effectiveness depends on air circulation. Allow sufficient clearance around the unit 

(recommended >50cm) to facilitate dry air flow. For large workshops, deploying multiple dehumidifiers in a distributed layout 

often ensures more uniform humidity control and superior performance compared to a single high-capacity unit.

Summary of Selection Decision Process

Standard high-temperature/high-humidity workshops (temperature <50°C, target humidity >40%RH): Prioritize high-temperature-resistant 

refrigerant dehumidifiers for cost-effectiveness, meeting most moisture control and drying needs.

Extreme high-temperature environments or ultra-low humidity requirements (higher temperatures, or dew point <5°C and humidity <40%RH): 

Desiccant dehumidifiers offer greater reliability, particularly for process drying.

When inexpensive heat sources are available (e.g., factory waste heat, steam): The economic advantage of desiccant dehumidifiers becomes 

significantly pronounced, potentially resulting in lower long-term operating costs.

Finally, it is recommended to provide your specific operating conditions (space volume, temperature/humidity range, process requirements, 

energy conditions, etc.) to a professional equipment supplier. Technical personnel will perform precise calculations and design a tailored 

solution. This is a critical step to avoid wasted investment and ensure the efficient and reliable operation of the dehumidification system.