If a dry winter climate has your humidifier chugging along full steam ahead, it's important deep clean it regularly. All that water makes these appliances prime places for growing mold and microbes. Let it go long enough and your machine could pump out bacteria along with mist or steam. At least once a week, turn off your humidifier and get cleaning — but you can do it more frequently if you or anyone in your family has respiratory problems.
To keep your humidifier in tip-top shape, we consulted Carolyn Forte, Director of the Home Appliances and Cleaning Products Labs at the Good Housekeeping Institute, for the basic steps you'll need to take depending on the kind you have. "It’s always best to follow the cleaning directions of your model," she says. "The key, whatever the type, is to clean and maintain it regularly. Stagnant water is a magnet for bacteria growth and you don’t want bacteria spewing back into the air, especially if family members suffer with asthma or allergies."
Forte recommends holding onto the owner's manual for specific maintenance instructions (at least until you get the hang of it). If your instruction booklet is long gone, you can contact the manufacturer or consult their website, but here's the basic gist of what you need to do.
What you'll need
You don't need (and shouldn't use) detergents or abrasive brushes to clean a humidifier. Just gather up the following:
- Distilled white vinegar
- Liquid chlorine bleach
- A small, soft brush, like a toothbrush or nylon dish brush
How to clean your humidifier
Note: Don't try to wash the wick filter as it can damage the paper-like material and potentially remove an antimicrobial coating. You're better off replacing the filter with a new one.
Both cool mist and warm steam humidifiers use a similar procedure, but some of the parts may differ. Some brands may also have parts that are dishwasher safe. Check the owner’s manual to be sure.
Step 1: Unplug and empty the humidifier, and disassemble it completely.
Step 2: For the base and tank, pour one to two cups of undiluted white vinegar into the water tank and swish it around to completely wet the interior of the tank. (Some brands recommend a mix of white vinegar and water.)
Step 3: Place the vinegar-filled tank on the base (or, if your humidifer allows, pour vinegar directly into the base), and allow the vinegar to drain into the reservoir to loosen mineral build-up. Let stand for 15-20 minutes.
Step 4: Empty the vinegar from the tank and base and use a small brush to scrub crevices and remove any stuck-on mineral deposits. For small parts like the tank cap, wipe with a clean cloth or sponge dipped in full-strength white vinegar.
Step 5: Rinse all the parts thoroughly and air dry, then reassemble.
How to disinfect your humidifier
If you think your humidifier's in need of a deeper clean, you can also use a bleach solution to help kill lingering bacteria.
- Disassemble and clean your humidifier as outlined above.
- Mix 1 gallon of water with 1 teaspoon of liquid chlorine bleach. Pour ½ to ¾ of the bleach solution in the water tank and swish to wet the entire inside. (Some brands may recommend a mix of 3% hydrogen peroxide and water for this step.) If your humidifier has a second tank, do the same with the remaining solution.
- Place tank in the base and allow the bleach solution to drain into the water reservoir. Allow it to stand for 15-20 minutes.
- Empty the bleach solution from the tank(s) and base. Rinse with clear water until the scent of bleach is gone.
- Wipe dry and reassemble.
Humidifier maintenance tips
Now that your machine's in good working order, take these steps to keep it running smoothly:
- Always empty the tank and reservoir when the humidifier’s not in use. Bacteria can grow in as little as one to two days.
- To prolong the life of your wick filter, turn it over each time you fill the tank to keep the top from drying out and to help the filter age more evenly.
- Replace the filter every 30-60 days depending on condition and use, especially if it gets hard and crusty from water minerals, gives off an odor, or the moisture output of the humidifier decreases.
- Remove and discard the filter and ensure all parts are clean and dry before you put the humidifier into storage, per the manufacturer’s directions.