Hey guys, haven't really had to chance to post much (work too damn much) but wanted to say I've learned so much from you guys. I've got an issue on a rack that no one can give me a definite answer.
I've got a Hill Phoenix rack, +10 SST R22 Meat Rack with air reclaim going to a McQuay evap. It is running on a suction float with 4 15hp Copeland 3ds with 1 of them VFD controlled and a split condenser with hot gas defrost. With a RMCC controller.
My liquid level just will not stay constant in the receiver, constantly bouncing from 0 and flashing to 40% with reclaim on. With reclaim off the liquid sits right @ 40%. First thing I did was leak check, found a bunch of little stuff, all the B19 hot gas valves leaking, all 4 compressor heads leaking, ball valves, and receiver indicator gasket was leaking, all now fixed. I could not get any bubbles to show but some oil showing up so I believe they were small. Been all over the sales floor, on top of boxes, cases, in the Mcquay and condenser, no blowers to be found. No underground runs.
Went through the RMCC because I also had the rack over and under shooting its target suction. It was all over the place. Found the on delays way too high for the compressors, was @ 30s, changed to 3s. Someone also put a -25# offset in the discharge transducer, changed the transducer offset back and changed transducer. It really smoothed things out, sitting right @ target now but liquid still going all over the place. Target suction @ 32# and Discharge is @ 190# with 20# shift in reclaim. Reset all my Sort's to store spec's.
I am in Florida so typical ambient in the day around 75- 85 and @ night has been any where from 55-65. I thought smoothing the rack out would help but really not much has changed. I keep wanting to pull my hair out, keep thinking I have a leak then I go upstairs and have somewhere around 30% in the receiver with reclaim on. Then the thing starts gurgling. Surprisingly all my cases are not warm even the last two on the header are achieving temp but today I pulled a strainer on the last circuit and it was plugged solid with crap. So I know I gotta be scraping bottom @ times.
So today right around 15:00 I noticed something but didn't have time to get into it as I just went on call for the weekend. I was leak checking the Mcquay heat reclaim AGAIN so I shut it down, my 3 way valve de-energizes and liquid goes up to 40%. So I force on the 3way valve to pressurize the coil, don't find anything and come back to the rack. The blower for the McQuay is now off, reclaim is on and the liquid level is staying dead nuts @ 20%. I actually had liquid coming back, it climbed up to 30% and stayed for 30 mins. It was maintaining 190 head but now ALL of my condenser fans were on. Then I said WTF, turned the blower back on, reclaim comes on and all condenser fans shut off and runs 190 head and there goes my liquid level again down the tank.
I just wanted to get some more opinions, everyone says my settings are correct, and they are, I was @ another store tonight with the same rack and set up and it is right. I've been told possibly the reclaim coil is too large, and to cut some passes out. I really don't want to do this because the store already has humidity issues and its only Feb. The store is right next to a damn swamp though. Then someone told me that my 3 way valve pilot line is possibly leaking by. But I really don't understand that one, and the guy couldn't really get into much more untill Monday.
Anyways sorry for the rant but this one has me stumped. Anyone seen anything like this before? Thanks for the help guys.