M&T Systems offers both an "Acidity System Restoration", and an "Oil Control" retrofit package for the revival of older units that might have previously been condemned. Using our proprietary techniques, M&T can breath new life into your aging Polycold refrigeration units. Giving you many years of extended service from your Polycold unit, and saving you thousands of dollars as compared to unit replacement.

Oil Control:

"High Reliabilty" Oil Control Retrofit

An Oil Separators function is to ensure the correct return of oil to the compressor's crankcase. In the early series of Polycold units, they relied completely on the refrigerant to do this, via integral phase separators. This worked fairly well when CFC refrigerants were in use, but later when the CFC's were eliminated due to EPA restrictions, the oil return began to suffer. Smaller units (e.g.; 330, 550, 660) had better tolerance for this, but the larger 1000-1100 series units did not. So in most cases only PFC-1000's, PFC-1100's or PFC-1101's will have a likely hood of experiencing oil related problems (e.g.; poor cooling and stuck solenoid valves).

To circumvent this problem, full-flow oil separators have been implemented in the compressor discharge path in the newest Polycold series (PFC-1102). This is not to be confused with the once standard smaller Temprite 902, or the later Polycold replacement for this same part. Since this was specifically targeted at creating an oil-free gas source for the Defrost circuit only.

In the newer 1102 design, oil laden gases exiting the compressor pass through two larger full-flow oil separators, before continuing on through the water cooled condenser, and into the autocascade heat exchanger stack. Unlike the older system where the oil separators were only used for hot gas defrost, the newer system also removes oil before it has a chance to freeze-up in the colder stages of the Polycold unit.

The Solution:
M&T will retrofit larger dual Temprite 905 full-flow oil separator's into your pre 1102 unit. This will provide a much improved oil return path to the compressor, and capture what ever residual oil had not been properly returned by the original system as built.

As part of this retrofit, we will also do a complete upper stage back-flush utilizing our proprietary reverse charging process. This will remove any pre-existing higher stage oil contamination that may exist, thereby giving the unit a clean start.

 Effective flushing is an important step in bringing the unit back to a "Like New" condition, and also for preventing contamination of the new parts that will be installed.

The compressor's physical condition will also be inspected for signs of internal wear, such as scored cylinder walls, or imminent valve failure.

 On very old systems, or ones that have had tenacious oil problems, it is highly recommended that the compressor be replaced as part of the oil control retrofit package.

The compressor oil will be changed to a new highly miscible synthetic, and the refrigerant charge will be updated to our custom high reliability blend.

 The original Zerol compressor oil was only miscible with 3 of the 6 refrigerants used in the original charge. So in other words; only 50% of the refrigerants in the original charge blend were effective at combining with, and returning oil back to the compressor. The "High Miscibility Replacement Oil" will combine with 80% of the refrigerants, and thereby exhibit a much higher rate of return.

Finally; we will also replace the liquid line dryer, and solenoid valves (rebuild kits will be used on Buffer and Hot Gas valves).

So if your Polycold unit has been diagnosed with chronic oil problems (e.g. stuck cool valves, warming up over time, lots of oil found in refrigerant lines). Please don't hestitate to contact us today, to see if our oil control package is right for you.