Why does the control panel of my essick air 7D6100 keep flashing 20? And how do I fix it?

That suggests a faulty sensor (or sensor connection) or controller board.

Are there no other symptoms, please?

Question edited for full make model (what it is)
Question moved from Dishwashers category.

It looks like there are no spares apart from consumables. Try the maker direct.

https://www.google.com/search?q=essick+ed11600+humidistat

https://www.iallergy.com/collections/humidifier-replacement-parts?constraint=essick-air
https://www.appliancefactoryparts.com/humidifiers/essick/ed11600.html

..

here's the manual for filter replacement......
https://www.manualslib.com/manual/49342/Essick-3d6-100.html#manual
google..Essick Air 3D6-100 Humidifier Replacement Genuine Wick Humidifier Filter #1040

I am battling the same trouble with this. I have re-booted the unit several times, and it is not a panacea. I am currently working on it, and will report here my findings.

Try adding a pinch of salt into the water. filtered water does not humidify as good.

Customer Reviews: Essick Air 821-000 Digital Control ...

www.amazon.com/Essick-Air...Humidifier/.../B0000D...

Amazon.com, Inc.Essick Air 821-000 Digital Control Evaporative Console Humidifier ... Holds 6 gallons and will dump 6 gallons in to the air over a 24 hour period, which ... a pain to fill, eventually leak, or come defective from the factory (holes on seams). ... We left itrunning all night, and barely any water had evaporated by the next morning.

Customer Reviews: Essick Air 821-000 Digital Control ...

www.amazon.com/821...Humidifier/.../B0000D8EJZ?...

Amazon.com, Inc.Essick Air 821-000 Digital Control Evaporative Console Humidifier ... So although notas dry as the northeast, it gets dry when the temps go down. ..... Had this humidifierfor less than three months and it started leaking all over my hard wood ...

Sorry to ask, for clarification is this a dehumidifier or a humidifier? Do you want to add water to your air or take water out of your air. A reading of 20 for a humidifier sounds pretty good to me. I didn't know there were filters on a humidifier, I thought most of the time you just filled the tank with distilled water, it got heated and vapor came out. I guess a filter to keep airborne bacteria from floating into the water tank would make some sense, maybe a water filter to pre-filter the water going into your humidifier, but I don't think any filter is your problem. If you are trying to remove water from your air, then a dehumidifier is needed and you just have to empty the tank when it's full.

mine is a floor model not a small one

I just changed the filter and it started flashing CF. How do you reset this other than changing the filter?

automatic, meaning it will self adjust as needed to keep the humidity level consistant