What to do with dehumidifier water, and whether you can drink it

What is in the bucket

A dehumidifier is a cooling coil and a fan. Room air crosses the cold coil, water condenses out of it, and it drips into the tank. That water arrives close to distilled, with almost no dissolved minerals in it. What it picks up comes afterwards, on the way: dust and whatever else is in the room air, the surface of the coil, and the tank it then sits in, warm, for hours or days.

That is the same device and the same water as an air conditioner's condensate, which the EPA has sampled. In its testing of condensate from building air handling units, heterotrophic plate counts ran from a thousand to ten thousand colonies per millilitre, culturable Legionella was found including the serogroup associated with Legionnaires disease, and at one site lead and copper were elevated because mineral free water is corrosive and pulls metal out of old plumbing. The drain pan biofilm was dirtier than the water.

EPA Science Inventory, water quality of air conditioning condensate, 20 September 2022 and March 2023. The longer version of this question, with the code references, is in is water from your air conditioner safe to drink.

Drinking it: no

Not as collected, and not after a filter jug either. A carbon jug is built for taste and chlorine, not for Legionella or lead. Boiling handles the microbiology and does nothing at all about metals. There is no approved route in the United States for turning condensate into drinking water, and the building codes that mention it list it under non potable sources.

If what you want is a second drinking water source at home, the honest comparison is in water from air or a rain barrel, and the short version is that a roof beats a machine by five to thirty times depending on where you live.

Watering plants with it: yes for ornamentals, no for the vegetable bed

This is the most common suggestion on the internet and it deserves a split answer.

House plants and ornamentals. Fine, and there is a real advantage: the water has no chlorine and no hardness, which some plants prefer. There is also a real disadvantage nobody mentions, which is that it has no minerals either, so it waters without feeding.

Anything you plan to eat. We would not. The uses that US rules list for captured condensate are irrigation in general, toilet flushing and cooling tower makeup, and no federal guidance endorses it for food crops. Given what the EPA measured in condensate, metals from the coil and pathogens from the pan, the conservative choice for a salad bed is tap water or rainwater. This is our reading of the evidence rather than a published rule, and we would rather say that plainly than dress it up.

2021 International Plumbing Code, chapter 13. Texas Administrative Code, title 30, sections 210.81 to 210.85, which allows condensate for irrigation, composting and flushing in homes with quality limits of E. coli below 14 MPN per 100 millilitres.

The uses that are actually good

• Flushing the toilet. Straight into the bowl, or into the tank if your local rules allow a connection. This is the biggest indoor use of water in most homes and it does not care about purity.
• Washing the car, the tools, the floor. Mineral free water leaves fewer spots than tap water, which is the one place the distilled character is a genuine benefit.
• Steam irons and humidifiers. They want water without hardness, which is exactly what this is. Clean tank first.
• Topping up an ornamental pond or a compost heap.

What all of these have in common is that nobody drinks it and nobody eats what it touches.

Keep the tank from becoming the problem

The water is better than its container. A tank that is emptied daily and wiped weekly is a different thing from one that has had an inch of water in it since spring.

• Empty it every day it runs, even when it is not full.
• Wash the tank with soap and water weekly, and let it dry.
• Keep the coil and the filter clean. The CDC's advice on devices that hold standing water is about exactly this: biofilm, corrosion and standing warm water are what let waterborne bacteria settle in, and the growth range it gives for Legionella, 25 to 45 degrees Celsius, is ordinary basement summer temperature.
• Store what you collect in a closed, labelled container, not an open bucket. Label it. Condensate in an unlabelled jug is how someone eventually drinks it.

How much will you actually get

It depends entirely on how much water is in your air, which changes by city and by season. In mid-July the air in New Orleans holds about 20.7 grams of water per cubic metre; in Denver it holds 8.5, and in January that drops to 2.4. Our water from air calculator gives the figure for your own city in both seasons, from NOAA hourly normals.

The practical shape of it: a damp basement in a humid summer fills a bucket fast, and the same machine in a dry winter runs for hours and gives you a cupful. That is not the machine failing. That is the air.

Sources, with the date of each

• EPA Science Inventory, water quality of air conditioning condensate, 20 September 2022, and the assessment presented in March 2023.
• CDC, controlling Legionella in devices that hold standing water, read 16 September 2026.
• 2021 International Plumbing Code, chapter 13, non potable water systems.
• Texas Administrative Code, title 30, sections 210.81 to 210.85, as summarised by the EPA, page updated 22 April 2026.
• NOAA NCEI, hourly climate normals 1991 to 2020, read 11 September 2026.

Said plainly: the advice against using condensate on food crops is ours, drawn from what the EPA measured. We did not find a federal rule that forbids it, and we did not find one that endorses it either.