Kite Refrigeration

R22 is now priced well above the alternatives. It will be getting more expensive every year, so the time to change to something new is upon us.

My goals are to not have more than two R-22 replacements that I need to stock. There are currently two families of replacements, one the R407* with two refrigerants, one for air conditioning and one for medium temperature refrigeration. The second family is the MO99 types, which are drop in replacements. There are medium temperature refrigeration and air conditioning types.

The 407C and siblings require a change in the oil, removing part of the mineral oil and replacing it with POE. New compressors for almost all applications now come with POE oil, and the replacement of the oil in an existing system is not too difficult. The last time we went through this with the CFC replacements taught us that being religious in removing all mineral oil was not necessary, in fact those who did it by the book caused themselves lots of grief as the POE oil lacked cooling and lubricating characteristics that the equipment at the time required. So a change would be to evacuate the R-22, change driers and any rubber seals or gaskets, change the oil in the crank case, then recharge with 407C. The system would have less capacity than R-22, and the head pressure would tend to be higher. The POE oil will clean the inside of the system, loosening up any oxide scale or anything else that is in the system, bringing it back to the compressor crank case. This is why filter driers are necessary. It will not be trouble free in all instances. The atom size of the HFCs is smaller, so an R22 system which doesn’t leak may with the new refrigerant. Systems that need all the capacity will have less, changing for example the balance point on a heat pump system.

The MO family of refrigerants have additives (some hydrocarbon) that will in most cases circulate the mineral oil. The rubber seals will need to be changed however. The capacity loss is similar to 407 C as well as the head pressure characteristics. The green house gas potential of this refrigerant is substantially higher than the 407* family. In some cases POE oil will need to be introduced into the system by an oil change to ensure adequate oil return.

I plan on using the 407C family of refrigerants. The oil changes and drier installs will insure proper oil return and filtering of the system.

In some cases, due to the age of the equipment it may be advisable to replace the system. These changeouts are not trouble free, and an old system may simply be not worth the time involved to sort out all the problems.

As for MP39, which we have used extensively as an R12 replacement, as well as a 134A replacement, we will be using an MO family. It has the added capacity that we enjoyed with MP39. We are stocking it and using it now. MP39 is very expensive and we will no longer be stocking it.

Some low temp systems use HP80, which is also becoming very expensive. We will be changing these systems to 404A which works very well. We will be working with our customers to prepare the systems for a change. The oil will need to be replaced, and there may be some capacity issues.

We can get R22 for the time being, and equipment is available for R22 as long as it isn’t shipped charged. This change will take some time; there is a vast amount of R-22 equipment in use. For customers who have multiple pieces of equipment we will change the systems gradually, reclaiming the R-22 for use in other systems until the lot is changed over.

The HCFC refrigerants and drop in blends will tend to become more and more expensive as time goes on. The HFC’s have become quite reasonable in cost. This tends to make the cost of changing more palatable. Systems whose operation are critical should be looked at and a plan of action decided upon. A failure may precipitate action, but if the last time was any indication, reliability is not guaranteed with the use of a new refrigerant.