I was looking at a broken newair for a friend a couple weeks ago and have been meaning to share my findings, it took a long time to track down any meaningful info so I figure I would save anyone in the future the time. He ended up getting a replacement control board from newair before I took a look at the control board but it would appear as though the issue is somewhere in one of the capacitors.
Interestingly it seems as though at least vinotemp and newair do not produce their own electronics they OEM them from a chineese company, I have read that this is the case with other major brands as well. I can confirm that for both thermoelectric vino temps and new airs the boards are interchangeable (obviously new-air 2801e and 280E have a different layout for the keys so they have different temperature control boards, however if you plug a temp control board from the 280e into a 2801e it will work fine it just wont fit in the door).
The problem he was having seemed to be in the temperature sensor, it would read the wrong temperature (it thought that it was colder inside of the wineador than it actually was, leading it to not turn on properly). It would have seemed like the issue was either a faulty thermister or something faulty in the temperature control board as it is responsible for reading the temperature and for switching the cooler on/off. Oddly replacing the main board which acts as a power supply as well as a switch for the fans, thermo-electric circuit and light, fixes the issue. I suspect that it is either feeding the wrong voltage or an inconsistent power signal to the control board causing the buggy behavior. I have yet to get around to measuring any of that yet.
From some discussions i found online (and will add links to a bit later) the culprit is usually a faulty capacitor somewhere in the main board.
This is board in question
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Here is a schematic that I found of it which was a big help in understanding what was going on.
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and a less detailed schematic in Chinese
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Given that it is a faulty capacitor more often than not, to get an idea of the scope of the job, here is a picture of them all I found.
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Here is a list of the relevant parts from mouser:
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Mouser #: 604-DA03-11PBWA/A
Mfr. #: DA03-11PBWA/A
Desc.: LED Displays & AccessoriesBlue diffused 2 Digit
1 $5.47 $5.47
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Mouser #: 511-STPS2045CT
Mfr. #: STPS2045CT
Desc.: Schottky Diodes & Rectifiers2X10 Amp 45 Volt
1 $1.21 $1.21
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Mouser #: 647-UVY1E222MHD
Mfr. #: UVY1E222MHD
Desc.: Aluminum Electrolytic Capacitors - Leaded25volts 2200uF 12.5x25 20% 5LS
1 $0.67 $0.67
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Mouser #: 647-UVK1H220MDD
Mfr. #: UVK1H220MDD
Desc.: Aluminum Electrolytic Capacitors - Leaded50volts 22uF 5x11 20% 2LS
2 $0.10 $0.20
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Mouser #: 140-REA470M1HBK0611P
Mfr. #: REA470M1HBK-0611P
Desc.: Aluminum Electrolytic Capacitors - Leaded50V 47uF 20% 6.3x11mm
4 $0.09 $0.36
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Mouser #: 140-SEA1R0M1HBK0407
Mfr. #: SEA010M1HBK-0407P
Desc.: Aluminum Electrolytic Capacitors - Leaded50V 1.0uF 20% 4X7mm
3 $0.09 $0.27
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Mouser #: 140-RGA4R7M1HBK0511G
Mfr. #: RGA4R7M1HBK-0511G
Desc.: Aluminum Electrolytic Capacitors - Leaded50V 4.7uF 105C 5x11mm
4 $0.08 $0.32
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Mouser #: 661-EKXJ201ELL121MK3
Mfr. #: EKXJ201ELL121MK30S
Desc.: Aluminum Electrolytic Capacitors - Leaded120uF 200Volts
2 $1.48 $2.96
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For reference this is the discussion that i found a lot of the above info in
http://forum.allaboutcircuits.com/th....101748/page-3
You might want to also check this out which is a pretty good explanation of how the board works, it's in portugese but if you use chrome or go to google translate and enter the url it will translate it without too much trouble.
https://dicasdozebio.com/2013/12/01/1547/
Here is the service manual that vinotemp provides that is a little hidden on their page
http://www.vinotemp.com/Resources/Do...Ds_service.pdf
It is also worth noting that while new air and vinotemp provide the same parts new air charges much less. Sadly even though I found the original part online on sites like aliexpress it seems to be more directly. Which is good info to know if you just want to replace the board.
I also during this process decided to make a schematic for the temperature control board which I will attach here, I have can make a color version later so it's easier to read. Also the chip all the way to the right is a 7 segment display I didn't feel like making a custom part.
Never mind it will only let me do 5 pics in a post, I'll add the schematic in the next one.
Also if anyone has any use for an Eagle cad version of the temp control board let me know
My plan is to design a replacement for the temp control board that displays temperature as well as humidity and overcomes some of the limitations of the current one (69 is the max and also the problem with them resetting to 54 when the power goes out) because I think it will be interesting. I have more or less designed the board, need to get out some calipers to measure everything and work on the layout a bit and decide exactly how i want to handle the software.
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