I need to clean the fan on my 8 gal. kenmore humidifier, but regular screws are not used to attach the cover of the fan to the rest of the filter cover. An alan wrench is also not the right tool. Anyway, how to I get to the fan to clean it? I haven't been able to use it because I don't want dirt and dust to be put back into the air. If I need a special tool, where do I get that?

It all depends on a couple of factors.

First is the type of humidifier your using. Portable or whole house connected to the furnace. Steam, ultrasonic or filter. Your unit's instructions is the best guide as to how often you need to clean it and this can vary from every day to once a heating season.

My recommendation is to watch and clean the unit as soon as you see scale forming. Then in the future, reduce this to just before you see scale forming.

The second is the type of water you are using. Hard tap water is the worst and usually will require every day for small portable steam or ultrasonic units to once a week for filter models. For central whole house humidifiers, once a month (perhaps as little as every two weeks if your water is really hard, >10 grains hardness). There is no fixed formula for this, the idea is to perform on-going, preventive maintenance.

Soft or conditioned water will contain the same amount of minerals as hard, but the softener has replaced the calcium minerals with sodium minerals. (Sodium bicarbonate actually).The result is the humidifier will still form scale but it much easier to remove. With soft water scale, you can just break up the scale with your fingers and the filters can just be submerged in clean water and the salt scale will re-dissolve.

Third, with distilled water, you may only need to clean any of these units annually. (No minerals to for scale).

With any filter humidifier, consider using a commercial bactericide to prevent the growth of bacteria when the water sits for long periods (>14 days). Not so critical with soft water as the salt will retard the growth of bacteria, but very important with hard or distilled water. Don't use this product in ultrasonic or steam humidifiers as it will be carried into the air along with the water vapor, and can be considered as toxic.

With hard water, use a 50/50 solution of white vinegar and water to dissolve the scale buildup. This works best if done on a regular basis. If left go too long, it become impossible to clean properly. You need only use regular water when using soft or distilled water in your humidifier.

you can unplug the unit,then remove top cover rear screw,then 6 screws on side of front grille,then all screws around the rest of the units wrap around cover,being careful to not stress any wires in doing so,then carefully blow out inside components out with low pressure compressed air or a vacuum cleaner

According to the Owners Manual, there's no way remove the top covering the fan. Just clean with a damp cloth and then wipe it draw. However, before wiping it with a damp cloth, you may want to try blowing out the sections of the grill with some canned compressed air with a straw nozzle (like you clean your computer with). Or use a vacuum cleaner with a hose and brush attachment. After doing that, wipe with a damp cloth and then a dry cloth.

If you need a copy of your Owners Manual, you can download and print it from the following website:

http://www.hunter-humidifiers.com/manuals/33250.pdf

you have to pop the cover off of the top if there are not screws holding the cover on then it should pop off with a screwdriver or you can use compressed air in a can that they sell in stores for cleaning computers

TRY POURING IN SOME WHITE DISTILLED VINEGAR AND RUNNING IT. THE VINEGAR LOOSEN UP ANY SCALE AND JUNK. AFTER RUNNING UNIT FOR AWHILE, DRAIN OUT ANY REMAINING LIQUID AND ADD DISTILLED WATER OR FILTERED WATER. RUN UNIT AGAIN. THEN DRAIN OUT ANY LIQUID. NOW THE UNIT SHOULD WORK AS NORMAL. IN THE FUTURE, TRY USING DISTILLED WATER OR FILTERED WATER.

there is instructions in the manual.here's a link:

https://www.manualslib.com/products/Kenmore-758-17006-3083394.html

From The Hunter 3322 manual.
1. Turn the humidifier ‘OFF’ and unplug the unit.
2. Lift the main housing and remove the water dispersion tray and the PermaWick™ Filters. The motor is attached to the main housing. Do not place the motor near water. Do not use a wet towel on the motor or motor housing as electrical shock may occur.
3. The PermaWick™ Filter should be cleaned in a vinegar and water solution to remove any mineral buildup. Place in a solution of one (1) gallon of water and eight (8) ounces of undiluted white vinegar. Allow the filter to soak for 20 minutes.
4. After soaking, rinse it several times with clean water. Place the PermaWick™ Filter in a location where it can drip dry while you clean the other parts of your humidifier.
5. Remove the water tank from the base and empty any water that is left in the tank. Soak the base in a mixture of one (1) gallon of water and eight (8) ounces of vinegar for 20 minutes.
6. After soaking, wipe the base with a soft cloth or sponge to remove any mineral build up. Rinse with clean water several times. If you are planning on storing the humidifier, be sure the base is completely dry.
7. Fill the water tank with one (1) gallon of water and eight ounces of undiluted white vinegar. Replace the tank cap and shake the tank vigorously until all interior surfaces of the tank have been exposed to the water/vinegar mixture.
8. Empty the tank of the water/vinegar mixture. Rinse it several times with clean water and then replace the tank cap. If you are planning on storing the humidifier, dry it inside and out, leaving the cap off to allow the tank to completely dry. Continue to clean the other parts of your humidifier.
9. Remove the water diffuser cap by squeezing the two tabs as shown in Figure 3. Rinse the cap in clean water to remove any debris. If the cap contains hard water residue, soak it in a mixture of one (1) quart of water and two (2) ounces of vinegar for 20 minutes. 41553-01 01/03/2008 6 © 2008 Hunter Fan Company
Rinse well and reinstall the water diffuser cap. Do not expose motor or other electrical components to water.
10. Wipe the surfaces of the main housing with a soft cloth.
11. Once all the parts are clean, reassemble the humidifier, and follow the USING YOURHUMIDIFIERto continue use. If you are storing the humidifier, make sure the parts are completely dry, reassemble, and store in a dry location

The instruction manual suggests using the water vinegar solution.
The following is from the manual.
1. Turn the humidifier ‘OFF’ and unplug the unit.
2. Lift the main housing and remove the water dispersion tray and the PermaWick™ Filters. The motor is attached to the main housing. Do not place the motor near water. Do not use a wet towel on the motor or motor housing as electrical shock may occur.
3. The PermaWick™ Filter should be cleaned in a vinegar and water solution to remove any mineral buildup. Place in a solution of one (1) gallon of water and eight (8) ounces of undiluted white vinegar. Allow the filter to soak for 20 minutes.
4. After soaking, rinse it several times with clean water. Place the PermaWick™ Filter in a location where it can drip dry while you clean the other parts of your humidifier.
5. Remove the water tank from the base and empty any water that is left in the tank. Soak the base in a mixture of one (1) gallon of water and eight (8) ounces of vinegar for 20 minutes.
6. After soaking, wipe the base with a soft cloth or sponge to remove any mineral build up. Rinse with clean water several times. If you are planning on storing the humidifier, be sure the base is completely dry.
7. Fill the water tank with one (1) gallon of water and eight ounces of undiluted white vinegar. Replace the tank cap and shake the tank vigorously until all interior surfaces of the tank have been exposed to the water/vinegar mixture.
8. Empty the tank of the water/vinegar mixture. Rinse it several times with clean water and then replace the tank cap. If you are planning on storing the humidifier, dry it inside and out, leaving the cap off to allow the tank to completely dry. Continue to clean the other parts of your humidifier.
9. Remove the water diffuser cap by squeezing the two tabs as shown in Figure 3. Rinse the cap in clean water to remove any debris. If the cap contains hard water residue, soak it in a mixture of one (1) quart of water and two (2) ounces of vinegar for 20 minutes. 41553-01 01/03/2008 6 © 2008 Hunter Fan Company
Rinse well and reinstall the water diffuser cap. Do not expose motor or other electrical components to water.
10. Wipe the surfaces of the main housing with a soft cloth.
11. Once all the parts are clean, reassemble the humidifier, and follow the USING YOURHUMIDIFIERto continue use. If you are storing the humidifier, make sure the parts are completely dry, reassemble, and store in a dry location.

There are 2 filters on each side. They are simply stood up right in the tank and the Black Circular fan shields rest on top of them to keep them in place.