McQuay Water Cooled Chiller

[Mleclerc]

I maintain Several new buildings, most were had the mechanicals done by the company that i am working for, with some of the specialized items getting Sub contracted out like installin the chiller in the basement and doing the Controlls for it. That said i had a call that the AC wasn't working in a few suites and found there Fan coils working fine, but i found the chiller in the basement had been shut down on an Alarm "Evaporator Water Flow loss". i cleared the Alarm and brought the unit back up, its been running with out issue for 2 weeks now. My concern is whether i should bring in our outside tech to look at the unit, he was in looking at it around the 10th of decemeber and didn't say anything was wrong. the pics are of the data screens on the unit My concern is the way the Oil preasure drops like a rock, as well as the "%RLA"? on the motor.

Any Advice? I am a plumber/gas fitter but not a refrigeration techie.

http://i581.photobucket.com/albums/ss257/Grnscrpn/Mcquay%20water%20chiller/Mcquay.jpg
http://i581.photobucket.com/albums/ss257/Grnscrpn/Mcquay%20water%20chiller/Mcquay8.jpg
http://i581.photobucket.com/albums/ss257/Grnscrpn/Mcquay%20water%20chiller/Mcquay7.jpg
http://i581.photobucket.com/albums/ss257/Grnscrpn/Mcquay%20water%20chiller/Mcquay6.jpg
http://i581.photobucket.com/albums/ss257/Grnscrpn/Mcquay%20water%20chiller/Mcquay5.jpg
http://i581.photobucket.com/albums/ss257/Grnscrpn/Mcquay%20water%20chiller/Mcquay4.jpg
http://i581.photobucket.com/albums/ss257/Grnscrpn/Mcquay%20water%20chiller/Mcquay3.jpg
http://i581.photobucket.com/albums/ss257/Grnscrpn/Mcquay%20water%20chiller/Mcquay2.jpg

[r404a]

could be when the chiller was going out on flow

[commloss]

the question was if you should bring in an outside tech....if you have a chiller you absolutely need regular inspections by a qualified tech. what model is that?

[triggerhappy]

I must commend you on the toughness of your post.

It would seem to me that you are loosing water flow. Determine what is controlling the pumps to start with.

Then you can go from there.

[Mleclerc]

The model is a WCC 063 Duel Compressor chiller, it runs year round serving two building's, approx 125 residence's in the building each having 1-3 fan coils. the buildings are less then 3 years old and very warm, most people don't turn the heat on in the winter and use the AC year round. the taller of the the two towers has an Evaporator on the roof.

I According to the second Picture everytime the unit cycles on the Amps on the motor(Yellow) hits the roof, and the Oil pressures jumps way up then drop like a rock. Is this normal for these units?


We do have a the Qualified tech that does the service and programing on the unit, but he only shows in May and in November.

[INTECHBILL]

You must have this checked on a regular basis or you can pay alot more later , if it was a water loss the first to check would be your expansion tank and with changes in water temps - this needs to be calibrated and level filled / droped almost all the time..., Pay now alittle or Pay alot later :argue:

[Randy S.]

The alarms are all loss of chilled flow, and one maybe a power bump or overload trip in the starter.

Are the pumps controlled by the chiller, as McQuay and most everyone else recommends? Variable or constant flow? If it's a VFD the minimum speed needs to be set properly for minimum design flow.

If they're controlled by a DDC system external to the chiller, you need to get to know who's who and what's what.

Is the chilled side make up keeping the system full of water?
Are the auto air vents functioning?

[heavymetaldad]

It's in the bas

[triggerhappy]

I must commend you on the toughness of your post.

It would seem to me that you are loosing water flow. Determine what is controlling the pumps to start with.

Then you can go from there.

Sorry about that. It's obvious that I can't spell.
It should have been "thoroughness"