Trane RTAC POE oil

[drillman]

We have three 400 ton RTAC chillers that are 3 years old with 134a.

Last year they had the butterfly valve leaks and one went flat.
A contractor changed them out on all three chillers.
All went well.

Had the yearly service done and that included an oil analysis.

Last year all chillers before the valve issues had about 125 PPM of water.
Now they got 500 to 600 PPM.

Can anyone tell me is that is going to be a problem?
What level of water is cause for concern?

How to dry out? Just replace the drier cores?

I am getting conflicting opinions from people on this and need clarification.

Thanks

[Tech Rob]

I've seen some issues with moisture contamination while the sample was in transit. If you're going to pull oil samples on these machines, you need to use a glass bottle with a gasketed cap. There are no drier cores to be replaced on any RTAC manufactured before 2011, either. Because of POE's affinity for moisture, the oil is the drier in the system. I have a document somewhere with the numbers. I'll try and find it for you. Paradoxically, R-134A systems are more forgiving than R-22 systems where moisture is concerned.

If the circuit went flat and was allowed to sit open for more than a day or so, I would have recommended an oil change on this circuit.

[jayguy]

if there is ever a concern with an oil sample, then you need to resample. another oil sample and report is much cheaper than any chiller repair.

[r404a]

rob

we use national for our samples, who is supplying you with a glass bottle

[r404a]

300 ppm I believe is max trane wants to see on oil48. change oil. is moisture indicator at exv yellow? if so, maybe a bypass filter, have a hose leaving the liquid line angle valve with a flare dryer, 303, entering into 3/8 line at the bottom of the evap and just crack the valve open at the evap.

[Dallas Duster]

So is the single core shell empty ?

I've seen some issues with moisture contamination while the sample was in transit. If you're going to pull oil samples on these machines, you need to use a glass bottle with a gasketed cap. There are no drier cores to be replaced on any RTAC manufactured before 2011, either. Because of POE's affinity for moisture, the oil is the drier in the system. I have a document somewhere with the numbers. I'll try and find it for you. Paradoxically, R-134A systems are more forgiving than R-22 systems where moisture is concerned.

If the circuit went flat and was allowed to sit open for more than a day or so, I would have recommended an oil change on this circuit.

[r404a]

think its a strainer

[Tech Rob]

So is the single core shell empty ?

It's not empty, but it has a paper filter cartridge in it. It's just there to catch debris. There is a very small strainer in the scavenger line going from the evaporator to the compressor.

[R123]

There is only a paper element in the single core shell. There never was a drier in there (even before 2011). Don't put a drier in there. If cleanup is needed, make a cleanup kit by putting a drier and sight glass between the liquid line and bottom of evap like R404a described.

[milkyway]

And I believe that this scavenger line has to have a slope ., I recall a SB on this.

[drillman]

Thanks for all your help.

Never knew there was not a drier in there, these machines are new to me.

Most of my chiller experience up to now has been with RTAA machines.

I will take the cheap route and send the oil off to another lab for retesting and see what happens.

BTW the lab that we got the results from states 200ppm of water is the upper limit.

Got a call into Trane to see what they think but the local office is not real good at responding real fast.

[jabeu]

Funny you mention a glass bottle. We get and send our oil samples out to Trane and they give you plastic bottles in the kits. above 300ppm is cause for concern.

[Tech Rob]

There is only a paper element in the single core shell. There never was a drier in there (even before 2011). Don't put a drier in there. If cleanup is needed, make a cleanup kit by putting a drier and sight glass between the liquid line and bottom of evap like R404a described.

The drier I was referring to was the one added to replace the 3/8" wye strainer in the scavenger line.