How to Add Vinegar to Humidifier Water to Keep Away Bacterial Growth

Hunker may earn compensation through affiliate links in this story.
You can safely use vinegar for cleaning a humidifier.
Image Credit: Helin Loik-Tomson/iStock/GettyImages

The internet abounds with people keen to give healthy alternatives for modern living, but the tips can be ill-advised or unsafe. Among these many helpful suggestions is that adding vinegar to a humidifier can somehow make household air fresher, but doing so can be dangerous.


Why Add Anything to Humidifiers?

Humidifiers are terrific when you live in arid locations, but they have annoying upkeep. After all, moisture breeds bacteria, which you know if you've ever left a wet washcloth sitting in a corner for too long. It stinks and gets downright foul, doesn't it? If your humidifier smells, odds are it's not the water that's the problem.


Video of the Day

Bacteria and mold breed inside humidifier tanks and it only takes a couple of days to occur — then you turn the unit on, unwittingly sending bacteria into your household air. Humidifiers are bad for your lungs if you don't clean them, so much so that the Mayo Clinic cautions people to speak to their doctor before using one if they have asthma or allergies.

So Why Use Vinegar?

Ironically, it's lung health that people gravitate to vinegar for because it's so effective for cleaning while being less toxic than commercial cleaning agents. The trouble is that vinegar can still be toxic. At levels over 5 percent acetic acid, distilled vinegar fumes can be hazardous to those with health issues — and dangerous to anyone when mixed with other cleaning products or bleach, which can create chlorine gas.


Breathing vinegar long-term isn't great, so using vinegar in a humidifier to "clean the air" actually does the opposite. But you can safely clean your humidifier with it.

Cleaning a Humidifier With Vinegar

You can use regular household 5-percent-acetic-acid distilled white vinegar for this, but a 6 percent solution is actually 20 percent stronger and better for killing bacteria. Note that 6 percent solutions are specifically cleaning vinegars and aren't safe for human consumption or gardens.


Step 1: Empty and Dismantle the Humidifier

Unplug the unit; then follow the manufacturer's advice on safely emptying the water from your reservoir. If you notice grime or grunge anywhere, that's a clue that cleaning is overdue — let it inspire more frequent diligence in the future.

Step 2: Treat the Base of the Humidifier

Mix a 50-50 solution of water and distilled vinegar; then fill the base with it. Let the base sit with the vinegar inside it while you clean the rest of the unit.


Step 3: Start on the Reservoir

Helpful here are cotton swabs and bottle brushes for getting into corners. Take the lid off and add 2 cups of undiluted vinegar and use your bottle brush to give the inside a good scour. Put the lid back on and vigorously shake the reservoir for as long as your arms can handle it. A few minutes will do for loosening all the hard-to-spot residue.


Step 4: Drain and Rinse the Reservoir

Turn the reservoir over so the release valve is facing down; then press the pressure valve on the drain nozzle (that bit you always try not to bump when putting the reservoir in place). This allows the vinegar to drain out but also cleans the nozzle from the inside out while draining. Repeat this process with clean water to rinse it, but also let it drain by pressing the valve to open the nozzle.


Step 5: Finish Cleaning the Base

Empty the vinegar-water solution from the base. Then, apply straight vinegar to a soft cloth and wipe the base and crannies clean. Also wipe down the rest of the unit, including the inside and outside of the spout through which the mist rises. Set it all aside to air-dry and the last of the vinegar will evaporate.

A Few Final Tips

That's it! You're done. If you're really keen to have "fresher air," your humidifier must have an essential oil dispenser. Don't add essential oils or other aromatic concoctions to your reservoir as it could be hazardous to your health or might damage the machine.


The Mayo Clinic suggests using distilled water in the reservoir, which can help keep it cleaner if your area has hard water or known microorganisms in the water supply.



Report an Issue

screenshot of the current page

Screenshot loading...