Ice rink chiller low suction on one compressure causein it to trip compresser?

[echo20]

Haveing a problem with York chiller. It was oragnialy design for chilled water only. But York said it would be ok to run with glycol with low temps glycol. There is 1 W compesser and 1-Vcompressed system runs on R22normal opertion is suction pressure23# on one comprsser the other for some reason operates at 10psi suction. One comp is operating at suction 10# and trips on low suction the other 23# and works ok. THE expension valve has been changed 2x. And all seems ok for a while then sunction drops on one compresser drops I notice that expension is frosted. There is also a solnoid on the high side after the king valve for load sheadding. Could it be that its passing by causeing low suction?


Thanks

[beenthere]

Moved to Chiller forum

[klove]

I'm sorry that I'm in a bad mood tonight. That being said: It gets real old having to tell folks that if they want help, they need to give information on the operation of the system. "I've got a compressor tripping on low suction pressure, what should I do?", can lead you down about a thousand miles of roads paved with good intentions, but you'll never go anywhere.

p.s. The expansion valve is frosting because it's controlling refrigerant flow to an ICE rink.

[dgruber]

Need to also know the control sequence and stages of unloading per compressor, among many other system variables as klove mentions!

[yorktek37]

I'm sorry that I'm in a bad mood tonight. That being said: It gets real old having to tell folks that if they want help, they need to give information on the operation of the system. "I've got a compressor tripping on low suction pressure, what should I do?", can lead you down about a thousand miles of roads paved with good intentions, but you'll never go anywhere.

p.s. The expansion valve is frosting because it's controlling refrigerant flow to an ICE rink.

Don't you just love how blunt he can be:grin2:. However he is right! You can't troubleshoot on assumptions. remember what they said about assumptions in the movie Under siege 2!!
I think one of the major problems is the Glycol concentration for starters.

[echo20]

Could you please just explain how that would effect the operation? Right now its pure glycol. Does it need to be cut with water. What the normally used Sg..

[chiller mekanik]

Can you post a log??

[txhvac]

Could you please just explain how that would effect the operation? Right now its pure glycol. Does it need to be cut with water. What the normally used Sg..

If you're running glycol cut w/ water or not, you've derated your pump & chiller. The viscosity of glycol is very heavy. Which glycol are you running? Ethylene or Propylene? Doesn't make too much of difference, but propylene has a higher viscosity. Depending on the type chiller you're running you should be able to get a cut sheet of how much glycol to protect you down to X temp, and where to set your freeze protection down to. As long as your refrigerant charge is correct, components are working, & your set up on the glycol side properly according to what the manufacturer states...you shouldn't have a problem. Chiller & pump sizing also take into consideration. I am going to ECHO some other folks on here post a log sheet, and give some more info. Hope this can help.

[echo20]

Ok thank you very much I get some more info for you..

[JRINJAX]

One "wild guess" on where to look would be internal icing of the TXV due to a wet refrigerant charge. A good hard hit with a brass hammer on the valve body will shatter the ice and temporarily fix the problem, raising the suction pressure. Usually this means the suction pressure has been allowed to go into a vacuum.