Red light flashes compressor shuts off water full bucket flashes but external and internal tanks both empty. Sometimes the external tank gets a bit of water 1 cup or so then kicks out and light starts flashing.

SOURCE: red light is flashing continuesly

Ok I found a temporary solution. I opened up the unit (yes there are a lot of screws) I checked the float switches and they worked and even unplugging the water level wire connection to the main board did not get rid of the red flashing light. But if you unplugged the connection from the front panel to the main board but leave the infrared remote still plugged in the main lights and control are not on but you can still work the unit by remote. When in this configuration the compressor will come on and the unit will cool. So I think that part of the problem is on the front panel circuit board or maybe somewhere on the main board. But physically the compressor/relay/ switches work. A short term solution until I can get a new board.

Cheers!

SOURCE: red flashing light

Hello,

Had the same problem, thing shutting off after an hour, no water in the tank. I had the external tank attached, was always bone dry. What I didn't know was on the side, there is a slide out tray which acts as the internal tank. The lid to that tank activates a micro-switch which tells the unit that it's full. This tank was dry too, but the switch was getting jostled, casuing it to trip. I've taped down the switch now, and it's fine. I check the tank every few days, just to be safe, but it's never got any water in it. Hope this helps.

SOURCE: External tank not filling

I recently encountered the same issue. First off, with the external tank installed is there an icon on the display panel indicating the tank is installed?

No? Then the two sensors are not picking up the magnets in the the "arms" on the back of the tank. It's a poor design for sure, on my unit the tank does not sit flush enough to the back of the AC, if I held the tank firmly to the back the icon would come on. I just used a bit of cardboard at the bottom of the support tray to press the tank firmly to the back of the AC.

Theory is as the external tank fills up, water will run into the "arms" and raise the magnets tripping the switch which tells the unit it needs emptying. But the magnets in the arms are not strong enough if they are not close enough to the sensors. So my cardboard solution lasted only one tank.

I ended up getting some flat neodymium magnets (that I scavenged out of a hard drive), and taped to the sensor that had the gap. I wouldn't recommend doing this to both sensors since it would eventually overfill, only one sensor needs to "trip" for the compressor to turn off.

If you answered yes to the first question (the bucket icon is there), then it's most likely the pump not working on the internal reservoir, or something related to that. Can't help you there...

SOURCE: When I turn on the ac, it beeps many times the red light says on

why did it fill up? because the drain is plugged there should be a safety switch that is keeping the comp off. find and clean the drain system.

SOURCE: danby standup aircondioner ( 3 in 1) , does not MODEL APAC9030

If you receive an answer to this I have the exact same problem... dougakers at msn dot com