CWR1661SZ - Wine Chiller Not Cooling

[lothian.mcadam]

I'm t'shooting a wine cooler that simply, suddenly stopped cooling. 

The unit powers up and controls (digital) work normally The compressor runs continuously, warm (not hot) to the touch, with no overload condition. I confirmed continuity across the r,s,c terminals. The relay is OK and the capacitance disk is intact. The compressor makes no unusual sounds (including typical refrigerant noises) and is not running "hot". High-pressure line is cool--not cold; low-pressure line is ambient temp. 

Evaporator is ambient temp and dry (no condensation); same with the lines to and from it. Condenser is ambient temp and clean (no dust). All fans run.

Manifold gauges indicate low refrigerant (suction side). I vacuumed the system for 2hrs, then left it under vacuum for ~24hrs (it held vacuum). The compressor drew in refrigerant (3.4oz max.), though extremely slowly. 

This unit has three temp sensors: defrost, and one for two "zones". The defrost sensor tests at ~18 Ω at 81°F, and 1 Ω (not ZERO) when I freeze it. I haven't tested the other sensors... yet.

There are other details I'm omitting for the sake of brevity, but that's the gist of things. I am stumped.


Suggestions? Recommendations.

[LearningTech]

 Your jumping around with your diagnosis.

in the future i suggest  getting an order of things before procedeing. 

For example: if the complressor runs, but no cool. There is no need to check defrost, ohm the compressor, check the relay, test the sensors, etc.

those things get in the way and i believe are  contributing to confuseing you.

 what matters (and you did good  in this) is pressures evap and condense temp.  Amp draw of compressor. Leaks etc.

[LearningTech]

 A few ?s i cant see much info on this... are we working with a single evap and fans to get to the zones, or is this a dual evap. Possibly with some sort of 3 way valve?

What do you mean by. 

On 6/6/2018 at 11:46 AM, lothian.mcadam said:

compressor drew in refrigerant (3.4oz max.), though extremely slowly. 

  Expand on this.  The compressor sucked it out of a bottle or. The pressure in the bottle let the refrigerant in?

 In low side or high side?

 What was pressures on both sides imi=ediatly after and after about 10 min?

did you weigh it in?

ALl that said, and from the info that the. Evap and  condenser have no heat exchange....i believe you have a plugged capilariy tube. 

Pressureise the high side port with nitro and. See if you have  any come out  low side port ( remove core)

 or your compressor could be rinning and not pumping, like bad piston or check valve.

[lothian.mcadam]

first off: thanks, LearningTech, for your replies. sorry for the late response. i never got notification of your post 'cause it appears i neglected to follow a thread that i started. d'oh!

the answers to your questions, in order...

the compressor appears to suck refrigerant out of the can based on can weight. the compressor may have also pumped the refrigerant from the can directly into the atmosphere since the pressure on the low-side reads zero. i suspect a leak.

i can only read pressure on the low-side; there's no schrader on the high-side, which is typical for these things. static pressure post-draw reads ~30psi and seems to hold; pressure drops when the compressor runs, of course. that the gauge shows pressure after 10 mins or 10 hours suggests no leak. however, there's also "no cool", sooo.... i'm considering the possibility of a clog in the line.

undaunted, i continued to pursue a leak diagnosis with a vacuum and dye. a vacuum might help to diagnose a leak but it provides zero help in locating it. for that i need a positive pressure test, and i simply do not have that equipment available to me. a positive pressure test would also help me flush the line(s).

so that's where i'm at with this thing.