Dehumifiier LAF VEAB not working

[PaulsM]

Hello. Maybe someone here could help me troubleshooting. This is a control of a dehumidifier. So, if machine is plugged in 230V, speaker on board makes a beep and It wont turn on, nothing works. I tested power regulator (third picture), its 7805C, input 18V, output 5V, fourth picture is datasheet for that regulator. Fifth picture is transformer, couldnt find datasheet for that, but it clearly says 12V, is that a problem? I guess not. What could I look for next? Fuse is OK. Curious to solve problem myself and learn something, thank you for your time in advance.

 

[PaulsM]

Hi. So, I managed to check every track on small board and all had 0 ohms. I probably should do it for large board as well? If microcontroller has supply and ON button is working, why wont it turn on (small board)..

 

[PaulsM]

Hey! I checked every track on both boards and all were good. Then I saw that hour meter is connected with a few hair of wire. I did not try to turn dehumidifier on before I made a good connection. Plugged in and it started to work. I disconnected hour meter to see if that was a problem - no, it still works. So, I didnt discover anything, but it works now... for now. I dont like that, I wanted to understand where the problem lies.

 

[betwixt]

Well done. Sometimes we have to put it down to Gremlins hiding in the dark corners but more likely your soldering fixed a bad joint, either on the wire or the board itself.

Brian.

 

[BradtheRad]

While the unit is working, take volt readings in spots where you got dubious readings previously in your diagnostic tests. Then you'll have normal operation to compare to in case it conks out again.

And yes there are times we fix something without knowing what we did or how we did it.

 

[danel25]

Hey! I checked every track on both boards and all were good. Then I saw that hour meter is connected with a few hair of wire. I did not try to turn dehumidifier on before I made a good connection. Plugged in and it started to work. I disconnected hour meter to see if that was a problem - no, it still works. So, I didnt discover anything, but it works now... for now. I dont like that, I wanted to understand where the problem lies.

Despite fixing a loose hour meter connection, the dehumidifier still worked strangely and you feel the root cause remains unresolved. Can you help brainstorm other potential issues causing intermittent functionality, even with a seemingly secure hour meter connection? Sorry for the late response.

 

[danel25]

Despite fixing a loose hour meter connection, the dehumidifier still worked strangely and you feel the root cause remains unresolved. Can you help brainstorm other potential issues causing intermittent functionality, even with a seemingly secure hour meter connection? Sorry for the late response. gb whatsapp pro

I think Intermittent issues in the dehumidifier's operation may stem from faulty sensors, a malfunctioning control board, or power supply irregularities.