Hi! I picked up my dad's wine cooler (Avantgarde, 12 btl) as it had stop working (no cool, dim/flickering display).

Board is HYS60-12-KD. Replaced a bunch of capacitors, a Schottky diode, and an sad old fuse.

The unit powers back up, it cool and all the fans work. The display is healthy and indicates the proper temperature as it goes down. All great!

Problem is, the fridge won't stop cooling past the temperature set on the display. Once it reach that temps it continue cooling and the screen shows '88' every second or so with both the red and green led flashing at the front. I guess it's trying to tell me there is an error...

I'm in a bit of a pickle here. What on the control board makes it stop cooling when the temperature is reached?

Any insights? Thanks!!

 

Problem in the temperature sense/control circuit, usually using a thermistor to sense temperature.
Post clear photos of both sides to the board so we can see what you have.

 

Could be a failure of the transistor or relay that controls when the cooling is on. The sensor appears to be working if it can display the temperature.

 

Problem in the temperature sense/control circuit, usually using a thermistor to sense temperature.
Post clear photos of both sides to the board so we can see what you have.

The front LED display indicates the correct temperature, which makes me think the fridge read the temperature properly.

 

Could be a failure of the transistor or relay that controls when the cooling is on. The sensor appears to be working if it can display the temperature.

Which relay or transistor controls the ON/OFF based on temperature?

 

 

That board was taken from the internet but it will do, except it is for 220-240 VAC input.

 

Have you followed the wires from the temperature sensor/display part to the main control board ? When you find out where these wires connect to on the control board you can trace what components are likely to do the switching. You could also check if the voltage on those wires chnges when the temperature is above and below the set point. This would tell you if the fault was on the control board or on the temperature sensing part.
Les.

 

These two schematics are basically showing the same thing.






The thermistor NTC1 is connected at CN4 in the upper drawing and CN2 in the lower drawing. The signal is amplified by U2A, LM358 and appears on pin-1 at RA5, 7.5 kΩ. It goes to the cathode of D19 and IC1 TL494CN, pin-1, also at the junction of R7 and R8.