engineered for efficiency, built to last
As a result, buildings remain unfit for use or occupation for many months, during which time high internal humidity levels can cause secondary damage and increase the risk of dangerous mould growths.
Whilst the drying rate of a material will vary according to its porosity and density, it is also determined by the ability of moisture to evaporate into the surrounding air.
Drying rates are greatly improved by lowering relative humidity, adding heat and increasing air movement.
Ideal drying conditions of 35 to 55 %RH can only be maintained if the dehumidifier capacity is greater than the rate at which moisture is being evaporated.
If the internal relative humidity rises uncontrollably (e.g., condensation on external walls and windows) it is a clear indication that the dehumidifier capacity is too small.
The majority of flood damage within the UK occurs in the colder months of the year. Many homeowners are often left wondering why the traditional refrigerant type building driers take so long to remove the moisture from the building following flooding. The answer is very simple, refrigerant type (condensation type) dehumidifiers are not suitable for operation at low temperatures due to the nature of how they work. In many cases, below 10.0°Cdb a condensing type dehumidifier, will remove little moisture as this sits below there efficient operating parameters.
Example...
Generic Condensing type building rental dryer - 450 m³/h
Capacity at °Cdb / Relative Humidity (RH)
30/80 = 49 Litres per day
30/60 = 32 Litres per day
20/60 = 16.5 Litres per day
10/60 = 10.2 Litres per day
5/60 = <5 Litres per day
From the examples above, it is clear that whilst condensing type dehumidifiers have a high removal capacity and efficiency when both the temperature and relative humidity is high, they rapidly lose capacity as the ambient temperature drops. During periods of even moderate temperatures, desiccant dehumidifiers will constantly out perform the condensing type. Below 15.0°Cdb ambient, refrigeration type dehumidifiers will also require to undergo regular defrost cycles, whereas desiccant type will continually remove moisture even at temperatures below zero.
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