And so now, the picture is starting to clear up a little.
Good point on delta across coil, we will see on a regular day temperature of 95, the entering air could be from 95 to 115 depending on were you are standing along the side of the unit between the two running. YES, there is definetly an air circulation issue. Anyoine want to take a stab at fixing it !!!!
picture three RTAC 500's side by side with 12 feet between them, mostly open area around them.
As for the oil temp. I understand the safety shut down, very well done. Now move me along into the load and unload of the female valve ????? I am recalling reading that valve was a 30% step after start up ?? Book not in front of me, so be polite about my memory !!
Keep it comin, and yes I can use probes to take temp readings, will mor then likly use a mop handle with a thermister taped to the end. May need an exstention thermister cord !!
It's impossible to over-stress the importance of verifying all condenser fans are running when they should. The only way to do it is climb up there and feel the air flow off each fan. Don't just walk it while looking down- feel it and make sure you're not feeling reverse flow. I have seen others make this mistake several times. Your mop handle with a short piece of string or ribbon may work, but you won't be able to also inspect the fan wiring this way. I think a combination of these two methods would be OK. I have 2 RTAC200's on my building's roof, about 100 feet apart, in Montgomery, AL. I've seen head pressure of about 210 psig at full load on a 95 degree day. Any hotter, both chillers are running.
the problem of high oil temperature and / or high pressure in a machine I had in Cancun, but was due to a high level of oil.
Good point .But if the charges of refrigerant and oil havent been monkeyed with my money is on the combination of dirty coils , wrong rotation and or non rotation of fans and air recirculation problems .
But if the history of the chillers is full of recharge and or oil issues etc etc . then it could be oil/refrigerant/noncondensibles etc .
You bend em" I"ll mend em" !!!!!!!
I"m not a service tech.. I"m a thermodynamic transfer analyst & strategic system sustainability specialist
Best Austin Healey In Show twice in 2013 .....All those hrs paid off .
I worked a startup on one of the first RTACs in our area central FL. It had very high head. After exhausting everything I knew and coming up empty I called tech support. Should have called first. They knew they had a problem. After sending data file and mod and sn conversation went something like this. Did you check the oil level on the separator. Yes is within the factory specified limits. OK do this remove oil until it is below min oil level. You can always add more. I removed over 5 gal oil before machine settled down. Apparently oil overcharge blows on through separator and trashes heat transfer on condenser from refrigerant side. Maybe it was just an isolated incident with new product etc,etc. If you have access to software level that you can graph and analyze operating conditions it will go a long way to understanding the problem. Otherwise call Trane. Could be a warranty issue or will be when you start loosing compressors.
The machines are spaced 10 feet between each at set of three each, so two sets of three, the three are seperated 10 feet, the sets are over 100 feet between. all are sitting on pads on the ground. no reall wall toubles. Today you could walk down between the two running side by side and see 110 air being sucked in........ Yep there may be a recirculation problem !!!!
We had (4) 400 ton RTAC chillers side by side, surrounded by a wall, and covered by a steel grate overhead. We suspected an air re-circulation problem. We used smoke bombs to visualize the airflow and confirmed re-circulation.
The customer added ducts on top of the fan deck to direct the discharge air up higher to get it away from the coils.
Hey "The Chiller Man", were did you place your smoke at, we did a simular test here and the smoke went in and up out the fans, I balieve they set them on the ground. I balieve it would be better to set them on the outer edge of the machine, up by the fans.
Also all, if ya bypass the VFD will the unit still bring in the relay and run the "A" fans......with out repograming ....
Also, we have those new interface pannels, touch screen, small ones, is it possible to reprogram at the screen with out a lap top ????
Need opinion on this:
You have a year round constant heat load, load average is 110 % split betweeen two machines 7/24. With O/A temps in the winter dropping as low as 25 but averaging 38 - 48, would you realy need the cond. fan VFD to be in place. I am looking at the cost of replacment of these items, verses doing away with them. We are seeing a replacment of at least one to two every lighting storm in the area. Lets face it, those VFDs are not the highest quality item on the market. .....
Next pet pea of mine now that I am working these little monsters, it the EXV. COME ON TRANE >>>>> a small tip of epoxy gell to hold the little plastic cover cap over the hole at the top of the head. Was washing one the other day and that littel disk came off, WELL, do ya really need me to tell ya what happens when water gets into the top of an EXV !!! Whats the in field remady for this one ???? We are going with the high dollar fix, called a 3' pvc pipe cap with a short piece of 3' pipe to set over the EXV........
Only problem is the PVC only comes in white !!! I'm gona paint them RED !!!
Any takers, place your order now, supplys are limited........... Custom colors are at a higher price.......