Chiller making popping noises?

[ulticool]

For some reason my chiller started making popping noises two days ago. When the compressor kicked on while playing games it sounded like it was popping popcorn. The compressor wasn't even warm to the touch wasn't loaded hardly at all.. I shut down and tried again still does it..

Is it low on refrigerant or something?

[flocko]

Can you tell the forum a bit about the system . Like some specs ?

Popping noise could be the compressor is flooding with liquid refrigerant . If the unit is running and does not have enough load to evaporate the refrigerant then the refrigerant will be sent (sucked) back to the compressor as a liquid . There are two things a compressor cannot compress , air and liquid !

Can you load the refrigeration unit with a source that will create more of a load (heat) ? See if it goes away with greater load .

Is it low on refrigerant ? Most likely not .... if anything , it would be overcharged for the current low load condition which as you you stated "wasn't loaded hardly at all" . However , if you impose a greater load, then (depending on evaporator temps , super heat and sub cooling ) you could be undercharged .

Need more info about the system first though .

-Flocko

[Drewmeister]

I'm assuming this is the chiller I built you. It sounds like the TXV is overfeeding the evaporator causing floodback. That could be due to decreased water/coolant flow through the loop, dirty condenser/faulty fan or a problem with the TXV or sensing bulb.

1) What is the coolant temperature when this occurs? Does it happen when the coolant is at room temperature? Which coolant?

2) Is the insulation still intact on the TXV's sensing bulb? The Bulb is located on the suction line exiting the top of the tank, right above the pump. See Pic.

3) Check the flowrate through the evap and your loop.

4) Insure that the condenser is clean and that the fan is operating properly.

[ulticool]

Originally Posted by Drewmeister

I'm assuming this is the chiller I built you. It sounds like the TXV is overfeeding the evaporator causing floodback. That could be due to decreased water/coolant flow through the loop, dirty condenser/faulty fan or a problem with the TXV or sensing bulb.

1) What is the coolant temperature when this occurs? Does it happen when the coolant is at room temperature? Which coolant?

2) Is the insulation still intact on the TXV's sensing bulb? The Bulb is located on the suction line exiting the top of the tank, right above the pump. See Pic.

3) Check the flowrate through the evap and your loop.

4) Insure that the condenser is clean and that the fan is operating properly.

1) Coolant temps get to about 17*c and the chiller kicks in and brings it back down to 9-10*c.

2) Insulation looks good, looks just the way you sent it.

3) Getting just under 4 gallons per minute through the loop. This is with both Iwaki's running.

4) No dust in the condenser fins and the fan is working good it looks like.

I have it on right now and it's not making the popping noises when the compressor kicks on.. same room temps and humidity and the chiller is set the same. I don't get it..

Additional Comment:

Well there it did it again chiller temps on the display were 16*c compressor kicked on and it started popping and stopped after 6 maybe 7 seconds.

[Drewmeister]

If the popping sound only lasts a few seconds upon startup then that would be transient liquid floodback. Why it started now after 1 1/2 yrs of operation... probably just wear on the TXV or some debris. A rotary compressor is much more tolerant to this than a recip.

I'll need you to test the unit under load at a setpoint of 23c, check for floodback and log compressor temps at the beginning(startup), middle and end of each cooling cycle. The load can be gaming or just loop Vantage. Run it for a few hours.

This will place a huge load on the chiller and will give us an idea how the txv is functioning. Stop test if compressor temp exceeds 90c or if the popping sound lasts longer than 15 seconds.

Btw, what is your room temp and approximately how long is the average off cycle? Have you added any extra fans to the unit?

EDIT: Sorry.. I meant a set point of 18c. We want the chiller to cycle On at approx 23c to 26c and OFF at 18c.