What Is a Refrigerant Dehumidifier
A refrigerant dehumidifier cools air using a refrigeration cycle to condense moisture out of the air. As warm, humid air passes over cold evaporator coils, water vapor condenses into liquid that drains away. The dried air then passes over warm condenser coils before being released back into the space. These units work best in temperatures above 60°F and relative humidity above 50%, making them ideal for active mold remediation projects in warm climates or during spring through fall in temperate zones.
Mold Remediation Application
During mold remediation, moisture control is critical to prevent regrowth. The EPA's remediation guidelines specify that indoor humidity should stay between 30-50% relative humidity (RH) to inhibit mold growth. Refrigerant dehumidifiers are particularly useful after water damage mitigation because they remove large volumes of moisture quickly. A standard 70-pint unit (extracting 70 pints of water per 24 hours) can handle a 500-square-foot area in moderate humidity conditions.
However, they have a notable limitation: efficiency drops significantly below 60°F. In cold or winter conditions, condensation freezes on the coils and the unit shuts down automatically. This is where desiccant dehumidifiers excel, as they function in low temperatures without performance degradation.
Moisture Control Protocol in Remediation
- Placement: Position units in the center of affected rooms, away from walls, to maximize air circulation around coils
- Duration: Run continuously for 48-72 hours after water extraction to bring humidity levels below 50% RH
- Monitoring: Use calibrated hygrometers to track humidity hourly during active remediation. IICRC standards require documentation of moisture levels
- Drainage: Either connect to a floor drain or empty collection tanks regularly to prevent backup and secondary water damage
- Ventilation: Combine with air movers and exhaust fans to create air circulation that prevents moisture from pooling in corners or cavities
Health and Safety Considerations
Mold exposure during remediation increases health risks, particularly for individuals with asthma, allergies, or compromised immune systems. By rapidly reducing moisture levels below 50% RH within 48-72 hours, refrigerant dehumidifiers help prevent mold spore colonization. This aligns with OSHA remediation guidelines for non-professional cleanups of areas under 10 square feet. For larger contaminated areas, professional mold remediation contractors use multiple dehumidification units alongside air scrubbers with HEPA filters.
Common Questions
- Can I use one refrigerant dehumidifier for my whole house? No. A 70-pint unit covers roughly 500 square feet in moderate humidity. A 2,000-square-foot home with significant moisture damage requires 4-5 units running simultaneously for 48-72 hours.
- What happens if I run it below 60°F? The coils ice over and the unit cycles off automatically. You'll get minimal dehumidification. If your basement stays below 60°F year-round, use a desiccant model instead.
- How often should I check the collection tank? With high humidity during active remediation, a 70-pint unit may fill its tank every 8-12 hours. Check every 6 hours initially, or connect to continuous drainage if possible.