Glycol leak into R134a system.

[Novema Kulde]

Hi, we have a big chiller/heatpump. strange things happened in the sightglass. oil analasys proved glycol in the refr circuit. shell and tube exch. was the culprit. this is now replaced. oil analasis did also prove some humidity of course, but no acid or other substances that indicated compressor trouble. compressor was still running when we decided to stop the plant. After replacing exch. we are pulling vacuum.. then!!! the vacuum oil starts getting almost white, after numerous vacuum pump oil replacements i sent a sample for analasys. it shows 690ppm glycol and 11000ppm water.....!!! way more than the oil sample from compressor... to think that the compressor (big bitzer screw) have circulated oil throughout the system for quite a while i'm afraid.... clearly we're getting more stuff out via vacuuming. Oil is getting slightly better, but i doubt we can remove remains this way.

Q: what can we do other than vacuuming until a sufficient level of vacuum is obtained? is there a cleaning possibility here? prohibited refrigerants we can rule out (R11 he he) maybe use the old R134a charge as a cleaning solution? idk the status of this refrigerant after being subjected to glycol. anyone who has gone through something like this? The unit is big, 2 compressors, 2 circuits and heating power of 800KW so to replace it would be very costly..... and it does not get any better that this is under warranty..... this is recipe of nightmare warranty.....

[The MG Pony]

you can use Isopropyle alchohol as a flush agent, it will have the added benifit of grabing the water and glycol and bring a good amount out with it, other then that heat and vacuum are the only real way to dry it, you can flush ofn to speed it up

then make sure to put on some over sized suction filter driers and keep a close eye on the system, if the oil loop allows it put a dehydrating filter on it as well.

[The Viking]

As MG P said above, Isopropylene Alcohol or there are various commercially flushing agents out there that will help, like EndoFlush (http://www.advancedengineering.co.uk/endoflush-flushing-solvent).
After you flushed it with a liquid alternative, OFN is bone dry and will absorb moisture so flushing the system with OFN is generally quicker than vacuuming alone to remove the moisture but will have little effect on the Glycol currently in the system.

Also, if you are considering reusing the refrigerant, pull it through a cleaning station that will separate oil and remove moisture before you put it back in to the system or at least push it in through several high quality driers, at least one of which should be a burnout one.


:cool:

[monkey spanners]

A cold trap before the vacuum pump would speed up the vacuuming process as would short and big bore vacuum hoses to the system.

I wonder if the Fri3oil machine would clean up the system?

http://www.fri3oilsystem.com/ingles/fri3oilsystem_definicion.html

[jason09]

definately ice trap , lots of nitro keep breaking vaccuum with it and heat