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Originally Posted by a.desisto

Is it possible someone has swapped out a compressor on this unit? The unit has 2 different size compressors in it now, maybe it was suppose to have more smaller compressors? Seen it before, and causes the unit to act like condenser is too small.

Good suggestion. Welcome to HVAC-talk. Go pro when you get more posts up.

Is it possible someone has swapped out a compressor on this unit? The unit has 2 different size compressors in it now, maybe it was suppose to have more smaller compressors? Seen it before, and causes the unit to act like condenser is too small.

You say that the condensers are clean, is the discharge air off the condenser fans straight up or hitting you in the face?

I agree with Lynn Comstock about the refrigerant purity and weight. If I don't know if it is correct, recover, change driers and weigh in the correct charge. When you check the charge by subcooling or superheat, the manufacturer says that the charge has to be close to begin with before using those methods to check and adjust the charge.

Have you verified with Trane that the fan blades are correct, the fans are turning in right direction and the fan blades are in the proper position in the opening?

Does this unit have low ambient dampers? If so are they open? Also make sure all fans are running the right way by climbing on top of unit. I have seen these run backwards because of a bad run cap you can't tell by looking at the fan it looks like its going the right direction. You must feel the air flow coming out to make sure its turning the right way.

Thx control dude I did check the unit and it does have the 5 blade fans and the amprage is actually a little over the full load amps of the condenser fans. I did check the pressure on the R-22 freon and there is no air in the system and I did remove the charge and weight it in to the name plate specks. I did however disable the smallest compressor and the machine runs and discharges the 55 degree air as needed by the building. I checked the coil at night to confirm that I could see light through the coil and it is clean (as I cleaned it myself) I have not had any issues once I disabled the compressor. I did however find out if the oat temps are over 95 degrees the unit has has problems for years. I also took a pressure drop across the condenser and I have a 25psi differance from the compressor discharge to the tap on the liquid line at the service valve.
Thx Guys for all the responses

Teckster, I don't remember the part # but there is a 5 blade cond. fan that needs to be on your unit due to the low airflow here.

Now I know who you are just call me when you get back from vacation!!!

If it helps any!

Hello, just thought I'd put my two cents worth if it helps. If both condenser coils are clean and match the unit, make sure that the motors and blades are original and match as well. Now if other people have messed with it, I personally would start from scratch and recover, remove old driers flush system with nitrogen make sure that there are no " Restrictions ", including in the metering device. Pull a good vacuum of 700 microns or lower if possible and charge with virgin refrigerant. After all you don't know what might be in the existing refrigerant. Well hope that helps and don't give up I'm sure you'll figure it out. It sounds like a restriction of some sort. Might be within the system, or circulation of air through the condensers. Check for distinctions or irregularity in the line sizes compare circuits. Good Luck!

Teckster, I don't remember the part # but there is a 5 blade cond. fan that needs to be on your unit due to the low airflow here.

Make sure all of the condenser fans are rotating the right direction. You will bypass a lot of the coil if one of the fans is running backward. There should be a noticeable temperature drop across the drier if it's restricted.

Could be:

Dirty coils
Wrong fan blades
Low load
Overcharge
Non-condensibles
Undercharge
Restricted driers

Or any combination of any number of the above.

I hope this is helpful. If it's not, post the following, and maybe I can offer more assistance.

constant volume or vfd? fan speed/static press.?
low ambient dampers?
return temp.
supply temp.
mixed air temp.
outside ambient temp.
suction press.
disch. press.
liquid press.
how many compressors running and which circuits?
how many fans running?
subcooling
superheat (all 3 of them)
press. drop across driers
clear sight glass?

Instead of the expense of ball valve and shell driers, recover, reinstall the relatively inexpensive factory recommended driers, and recharge?

Originally Posted by vanillaIce84

I can do that if it bothers you

Hello my friend and welcome to the forum!
It's not that it bothers him, but the person who started this thread is looking for help with his Trane unit and when you hijack a thread and change the subject, it takes away from the original person looking for help. Its no big deal, we've all done it (including me).

I can do that if it bothers you

Originally Posted by vanillaIce84

I'm new to commerical. So I have a lot to learn about walkins and econimizers. I don't understand yorks compressor lockouts. Is it only lock if low voltage amp draw is to high to it ? I don't understand how it sence the amps.

With all due respect, you hijacked the thread. Why not start a new thread and talk all you want about cti boards and York compressor lockouts.

PS. Welcome to the forum.

I'm new to commerical. So I have a lot to learn about walkins and econimizers. I don't understand yorks compressor lockouts. Is it only lock if low voltage amp draw is to high to it ? I don't understand how it sence the amps.

Yeah. I like working on Trans units. They are usually pretty easy. I hate Yorks, no field experience by anyone in the factory, the electrical panel is way to small.

Ok, ill check. It is a reliatel board. It is cool all the things u can do it just cost to much to replace.

It reconfigures the L.T.B for conventional thermostats. The pain in the neck is to see if your unit is pre 93 or after 93. They change where the wires land on the LTB

Thanks a lot. I have seen that cti but never knew what was for.

If you have the UPC board with the #'s and the letters. Yes you can switch to a conventional stat. If you have the UPC board with no connections on it, then you would need the C.T.I board. (Conventional Thermostat Interface)