Hi all you old refrigeration dogs. I am NANOTECH and I am new here and this is my first post. I look forward to contributing and learning! Here it goes.
I have a medium size supermarket just installed with older equipment. All Hill/Phoenix cases and Warren/Sherer Racks all R404a. Queston is on the med. temp. rack. Md# TD3-4005-TC-A Sn# 110361908 It has 3 copeland semi hermetic compressors on it. From left to right 1.) 3D53A150E-TFC-800
2.) 3D53R17ME-TSK-800. 3.) 4DE3A-2000-TSC-800. There are a total of 9 cuircuts with SORITS using off cycle defrost. Using a Danfoss AK-255 controller.
The case arrangement is as follows: 36' dairy, 24' dairy, 24' beer, 16' beverage, 24' produce, 48' produce, 48' low deck produce, 16' cheese island, 16' produce island. I do not know the btu rating per foot to calculate total btu's required wich leads me to my first question.
Question Number 1: How do I know that my total btu's at +15 SST header is enough to match total required btu's for the cases (load)? I am assuming that i need a +15 header based on a 10 deg. TD to maintain SORITS. I am not truely sure on how to determine what the target header temp should be?
I am gussing that the controller will stage the compressors according to the load and capacity based on the hp so I put in from left to right 15hp 15hp and 20hp. Set the suction target at +15 (50psig) and the discharge at 90 (205). Is this correct?
On start-up with the sight glass full and reciever level at 20% all cases at or below 35 my suction pressure is at 48 psig and 4 fans running on the condenser cycling one set on off to maintain 205 psig set point. (75 deg. ambient day)
Question Number 2: Is my suction to high due to being undersized? I do not seem to have quite low enough header pressure to set the SORITS. If this is the case would'nt my head pressure be to high also? I really do not want to run all the cases on rack pressure due to not having a t/stat or llv installed.
Hope this is'nt to much for a first post but it is where I am at. Greatly appricate any input. Oh by the way how do you post a pic with username?