The water collected by a home dehumidifier, known as condensate, is not safe to drink. The water produced by the appliance should never be consumed without extensive purification and sterilization. While the process of dehumidification initially separates pure water vapor from the air, the subsequent collection method introduces significant contamination, making the resulting water a health hazard. The appliance is designed solely to reduce indoor humidity levels and is not intended to produce potable water.
How Condensation Creates Contamination
A dehumidifier operates by drawing moist air over a set of chilled coils, similar to how condensation forms on a cold drink glass. This refrigeration process causes the water vapor in the air to condense into liquid droplets, which then drip into a collection reservoir or bucket. The air circulated through the machine is not filtered to drinking water standards.
As the air passes over the coils, it deposits various airborne particulates directly into the collected water. These contaminants include common household dust, pet dander, pollen, and microscopic mold spores. The dehumidifier coil and collection tank are not sterile surfaces; therefore, the water picks up any dirt or bacteria that has accumulated on the internal components.
The dark, stagnant water within the collection bucket creates a favorable environment for rapid microbial growth. Bacteria and molds can multiply quickly in this warm, damp setting. This biological contamination transforms the initially pure condensate into water unsuitable for human consumption.
Why Dehumidifier Water is Not Distilled
A common misunderstanding is that because the water is condensed from vapor, it is the same as distilled water. True distillation involves boiling water to create steam, which kills all biological contaminants and leaves behind all non-volatile substances like minerals and heavy metals. The steam is then collected and re-condensed into sterile, purified water.
Dehumidifier water, or condensate, only performs the condensation step, skipping the high-heat sterilization and purification process. While the condensation process naturally results in water with a very low Total Dissolved Solids (TDS) count, meaning it lacks minerals, it remains biologically contaminated. The absence of the boiling step means the water still harbors the mold spores, bacteria, and dust particles collected from the surrounding air. This lack of sterilization is the fundamental difference that makes dehumidifier water unsafe to drink.
Health Hazards of Ingestion
Ingesting dehumidifier condensate carries several specific health risks, primarily due to the microbial and chemical contaminants present. The warm, moist environment within the machine is an ideal breeding ground for various pathogens. Consuming water containing these organisms can lead to acute gastrointestinal issues, such as diarrhea, vomiting, and general stomach upset.
Beyond common bacteria and mold, there is a risk of exposure to more serious pathogens, such as Legionella bacteria, which can breed in stagnant warm water. Ingesting water contaminated with high levels of bacteria can still pose a danger, particularly to individuals with compromised immune systems.
Furthermore, the water may contain chemical contaminants leached from the internal components of the appliance. Dehumidifier coils are often made of metals like copper and aluminum, and over time, trace amounts of these heavy metals can dissolve into the collected water. Boiling the water to kill bacteria is not a solution, as it would only concentrate these non-evaporating chemical and heavy metal residues, increasing the danger of toxic exposure.
Practical Non-Potable Uses
Despite being unsafe for drinking, the low mineral content of the condensate makes it useful for several non-potable household applications. The lack of dissolved minerals means the water will not leave behind scale deposits, making it an excellent choice for appliances and cleaning.
Uses for dehumidifier water include:
- Use in steam irons or non-evaporative humidifiers.
- Mopping non-porous surfaces like tile or vinyl floors.
- Washing cars or cleaning windows, as the low mineral count avoids streaking.
- Flushing toilets, which conserves potable tap water.
It is generally not recommended for watering edible plants due to the potential presence of heavy metals and microbial spores.