Chiller Questions

So I was gifted a pair of Aqua Logic chillers, one is the 1/4hp version and the other is 1/3hp version, both without temp control. They haven't been fired up in a while but are intact and do turn on. I'm a total newbie to these things so I have no clue how they function or how tell if one is working as it should. The compressor appears to function right on one of them, one line is warm to the touch, the other is nice and cool, compressor itself is warm and humming along like it should. The other one needs a Schrader valve replaced on the low pressure line as it has a slight leak. I'm assuming that a new valve and a recharge will fix that one. My question really is, how do these things work? Is the coil that drops in the water supposed to get ice cold or does it simply absorb heat? Nothing on the unit is freezing cold as I though it would be, could this one need a recharge as well? If anyone could give me pointers on what a properly operating chiller should do/sound/feel like I would be very grateful. Also how does one go about checking if the refrigerant needs to be recharged? Oddly enough these have high and low pressure ports on them and are filled with r134a so recharging should be fairly basic. Thanks!

 

Just an update, I got bored and was able to get both chillers working perfectly. Picked up a retrofit kit for the low side ports and was able to recharge both units using an a/c recharge kit for a vehicle that I picked up at wally world.

 

This gives me hope, thanks.

 

We actually have an old AquaLogic 1/5hp drop-in chiller that works very well (we got it close to 10 years ago, used, for $90).

We use a Ranco dual-stage temp controller on it. One stage controls the chiller, and the other controls a heater. This configuration keeps the temp as stable as you can get it, and it ensures that the heater and chiller don't "fight" each other.

The way cooling works is via heat exchange, so the coil doesn't get freezing cold. This is why you need vent space in front and back of the chiller. Cool air in the front, hot air out the exhaust in the rear. Keep at least 12" clear on both the intake and exhaust sides of the chiller for best results.