Water in Refrigerant pipe

[nana191]

Dear all

Our water cooled water chiller have problem, heat plate exchanger condenser broken down and water come in refrigerant pipe.

Everyone have experiences about this problem, please some ideas to solve: remove water and bad oil on interior pipe surface and replace oil in crankcase.

Chiller: Hitachi water cooled water chiller
Model: RCUP43WUZ

[goshen]

hi sorry not so simple u need to replace heat exchanger ,probably replace your txv ,change filters ,clean system with nitrogen, then test it for leaks, and vaccume it down to 500 microns for 24 hours
and change oil
good luck

[NoNickName]

It's doomed. Forget about fix it. It will never be the same. Write it off.

[gas bottle]

Don't give up! Cut suction and liquid at both ends, warm/heat the pipework any way you can, blast through with dry nitrogen, flush with an ozone friendly flushing agent such as we use when changing over from R22 or R407C to R410A, change oil in compressor, fit rechargeable core driers with bypass lines in suction and liquid lines, fit a new moisture indicating sight glass, vac and vac and vac and when you think its dry vac again (a decent electronic Torr gauge will tell you when a deep vacuum is holding), replace heat exchanger and fit new TEV. Look for any controls/pressure switches etc that could be holding moisture and replace them.
When you re-charge the system and run it, replace the driers frequently.
You will get it to work, I know, I,ve been there.
Good luck

[lowcool]

gas bottle is on the money,my prefered heating method is an oven whilst nitrogen is purged through components.time consuming,100% effective and little time on the vac pump required if relying on this to remove moisture with no damage to your vac pump

[nana191]

Now, I'm repairing the Chiller as your guide:
- Replace new condenser (-- it's so expensive-- :confused:)
- Isolate controls/pressure sensor.

- Use Nitrogen purge refrigerant pipe:

However, Compound of bad oil and water adhere to pipe Interior surface so purging nitrogen can't clean inside completely although I use much nitrogen.

For this reason, I install two heaters on pipe external to heat all pipe, heat exchangers to ensure all water in compound will be evaporated and swept with purging nitrogen. I think it be more effective. However, it can burn bad oil and be reason of deposit.

This system does not have filter and bypass line - pipe diagram is in attach file.

- Replace old oil in screw compressor is also serious problem. Crankcase, oil separator and grease method is different than scroll comp.
I don't have Manual to replace oil because any dismantle will lose sealed of comp.

[goshen]

hi u must install a filter drier if u dont have one and change it often

[NoNickName]

Wasted money and time. Write it off, it won't work, whatever effort.

[nevgee]

Replace faulted condenser, remove all oil from system, purge with oxygen free nitrogen, fit new condenser, fit a liquid line filter drier, fit a suction line filter drier. then ..... vacuum pump the system until all moisture is removed, triple evacuate using nitrogen, and keep doing so until the system shows no rise on the Torr gauge ( 0.5 Torr / 500 micron or better without rising over say 24 hours)

when satisfied the system is dry, charge with oil and refrigerant.

There is no need in changing TEV and pressure switches as the vacuum pump wiill remove the moisture if you get it low enough.

If the cost of all this work is greater than the capital value of the machine then buy a new machine. Simple ;)

Good luck.

[nevgee]

PS screw compressors dont have crancases ... so there will not be any oil in there to drain out!

[lowcool]

flush the system components before dehydrating.most important!

[mbc]

the vacuum pump wiill remove the moisture from system but you should be vacuum it for long time. and you should chang oil

[goshen]

hi sorry not so simple u need to replace heat exchanger ,probably replace your txv ,change filters ,clean system with nitrogen, then test it for leaks, and vaccume it down to 500 microns for 24 hours
and change oil
good luck
as said before good luck

[NoNickName]

PS screw compressors dont have crancases ... so there will not be any oil in there to drain out!

Yes, they have. It depends on brand and model, but definitely they have crankcases.

[chris96]

You'll need to change the evap, most likely the compressor if water reached there(presume its a recip) all dryer cores, TEV will need changing. maybe the flow switch if this is what caused the evap to go in the first place. You'll need to drill the pipe-work in several places as the water most likely has moved around the pipe-work, where you drill in the pipe fit some schroder ports to fit your gauges too, this will give you more ports to vac off. Triple vac the system, changing the oil in your pump everyday for about 3 - 5 days. charge and run the system for about an hr, drain the comp oil, reclaim the gas, change the dryers again, then run for about two weeks the repeat the changes, then you should be good.

[lowcool]

a vac pump will remove moisture but not the crap that is associated with water induced to a system.i use shellite as a flushing agent its cheap and effective and by flushing you are removing moisture as well

[mbc]

I had same case before ((may be 6 times)) I used by vacuuming the system to remove water . I put system for 48 h in vacuum . ( not with vacuum pump – vacuum pump is not good for running for this much time ) I have small ( one piston ) air compressor I used that.
1- I tried to clean all pipes with nitrogen.
2- I put them for 48 H in vacuum.
3- I changed all filters((core dryer ))
4- I changed oils
5- After running system I changed 2 time core dryers

[Yuri B.]

shellite as a flushing agent
Is it safe for the motor winding insulation?

[Voyager]

Is it safe for the motor winding insulation?

Yes. The flushing agent is only used inside the system. it will not come into contact with the windings. (if it does, you have a serious leak !)

If you want to know more about flushing, try http://www.hecatinc.com/

[lowcool]

gday yuri i havent had winding failure yet,more likely to get it from not flushing.just converted my latest beer fridge including washing out of dome to 134a

[nike123]

I had same case before ((may be 6 times)) I used by vacuuming the system to remove water . I put system for 48 h in vacuum . ( not with vacuum pump – vacuum pump is not good for running for this much time ) I have small ( one piston ) air compressor I used that.
1- I tried to clean all pipes with nitrogen.
2- I put them for 48 H in vacuum.
3- I changed all filters((core dryer ))
4- I changed oils
5- After running system I changed 2 time core dryers



It would be almost same if you only changed core dryers.

What is vacuum level you achieved with that "small ( one piston ) air compressor"?
If you don't know your vacuum level, how will you know that water is actually boiling? Do you know what is required pressure (vacuum level) to boil water at ambient temperature? Did you ever reached that vacuum level with that "small ( one piston ) air compressor"?


( not with vacuum pump – vacuum pump is not good for running for this much time )On what facts you base this attitude?
My Refco double stage vacuum pump is almost 20 years old, and stil pulls to 80 microns, and it was used many times for non-stop vacuuming over one week (with regular oil change).

And, at the end, how do you know that you have acceptable water content (10-50 ppm H2O) in your "air compressor vacuumed" system.

What you presented here is, sadly, plastic example of bad evacuation practice (which I also watching here in my country at regular basis).
I suggest you to explore this forum little more for correct evacuation procedure and tools. It has plenty of material.
For example, this post (http://www.refrigeration-engineer.com/forums/showpost.php?p=162556&postcount=5).

[goshen]

I had same case before ((may be 6 times)) I used by vacuuming the system to remove water . I put system for 48 h in vacuum . ( not with vacuum pump – vacuum pump is not good for running for this much time ) I have small ( one piston ) air compressor I used that.
1- I tried to clean all pipes with nitrogen.
2- I put them for 48 H in vacuum.
3- I changed all filters((core dryer ))
4- I changed oils
5- After running system I changed 2 time core dryers


sorry mbc totaly disagree with u any good vaccum pump will do the job even a week non stop all u have to do is watch your vaccum oil and change it accordingly
u cannot compare vaccum to compressed air
by going into deep vaccum u boil all the water out of the system by using compressed air u might be doing just the opposite!!!!
the core drier replacment does indeed do the job !!:)

[mbc]

Dear goshen
Air compressor not for blow air to system , use suction side of that to sucks air,
I have 2 vacuums pump, one of them is original vacuum pump ( 1 hp) I use it for small systems , Another one I made it from bittzer compressor ( 4 hp ) I use it for large systems
Both of them go to deep vacuum and sometimes I use it for recovering gas.
The reason Why I use Air Compressor is , moisture is not effect and damage it and I had in my work shop.
If in your work shop you have air compressor you can test it . open discharge side , connect your manifold to suction side then measure it , might is not very deep vacuum but you see it is good vacuum.

[nike123]

The reason Why I use Air Compressor is , moisture is not effect and damage it and I had in my work shop.


What is vacuum level you could achieve in system with that air compressor or Bitzer "vacuum pump". Give us numbers in any pressure unit you like and it will be clear that is not enough for boiling of water at normal ambient temperatures.

http://www.engineeringtoolbox.com/docs/documents/926/water-pressure-boiling-temperature.png

Moisture wil also not damage vacuum pump. There is gas balast valve on any decent vacuum pump which is used in first moments of evacuation when moisture in system is presenting problem (from 20 to 3 torr). And frequent oil change is also necesary.

[goshen]

Dear goshen
Air compressor not for blow air to system , use suction side of that to sucks air,
I have 2 vacuums pump, one of them is original vacuum pump ( 1 hp) I use it for small systems , Another one I made it from bittzer compressor ( 4 hp ) I use it for large systems
Both of them go to deep vacuum and sometimes I use it for recovering gas.
The reason Why I use Air Compressor is , moisture is not effect and damage it and I had in my work shop.
If in your work shop you have air compressor you can test it . open discharge side , connect your manifold to suction side then measure it , might is not very deep vacuum but you see it is good vacuum.

hi there i do know there is a reason for us using vaccum pumps in our industry and as nike 123 said u need 2 boil out all the water!!! a standared air comp is not desigend for this job and i really dont know to what level of vaccum it will go ,so i would rather save time and use the appropriate machine for the job and be on safe side .;)

[mbc]

Dear Nike
I did not wrote Air Compressor and bittzer Compressor I am using as same as vacuum pump can go to deep vacuum, mainly moisture and water will remove by dry Nitrogen .
I large system as same as 3000 ton cold store NH3 it take loge time to vacuum it ( unfortunately I have not big one) by my small vacuum , So I use bittzer compressor to vacuum it then after running system
I do Air went action by manual or if I have air purge system by it
My Air compressor specification is D = about 80 mm stork = about 120 and I changed compress Ring
To Teflon graphite ring as same as we have in CO2 compressor and in oil free compressor.
Also I do not know , how I should measure moisture in system , if you have information please inform me .
To cover my this disability I have to change 2 times my Core Drier after running system
Also I change 1 time in ferion system Core drier when I put New system (medium and up system )
I am a little family with world standards ( I have 35 years experience 28 of that here and 7 of that in New Zealand) here sometimes is very difficult for us to find what we need so for some tolls

[nike123]

Also I do not know , how I should measure moisture in system , if you have information please inform me .


When you do vacuum drying you should monitor your process with electronic vacuum meter. It will tell you if you have moisture in system or not, and it will tell you even if you have leak in system.

http://farm4.static.flickr.com/3583/3838873919_aa134cc631_o_d.png

If moisture is present in system, it evaporate because of low pressure made by vacuum pump. If you isolate vacuum pump and alow some time that pressures equilise, if moisture is present, you will be reading water evaporation pressure, for that ambient temperature your equipment is, on your electronic vacuum gauge.

For example, if ambient is 20°C, after vacuum pump isolation, and some time is passed in which you will have rise of pressure, you will be reading steady 23.38 mBar at your vacuum gauge (17540 microns) if you have any non evaporated water. Remember that, if we have liquid and gas, than we have saturated state of mater, and therefore we have indication that water is present if we have water saturation pressure/temperature relation in system.

It is established that, if we have 2000 microns steady vacuum (2.66 mBar) that all water is evaporated (if ambient is above -9,74°C, which is water saturation temperature at that pressure) and that is equivalent of 50 ppm water vapor in our system. Also if we have 1000 microns (and ambient is above -17°C) that we have 10 ppm water vapor in system.

ppm= parts per milion

Your sight glass will change color at about 30 ppm of moisture (Castel for R407C, 404A, 410, 507) or at 60 ppm for R22.

Did you ever read this document for which I posted link to another post earlier?
http://www.mediafire.com/?zmyztx5gnzm

Also these are good readings:
http://www.yellowjacket.com/content/Articles/SuperEvac_Pulling%20Effective%20Vacuum.pdf
http://www.designair.com/resources/evacuation+clinic+show.pps
http://www.jbind.com/tools/userfiles/file/Deep%20Vacuum%20Principles.pdf
http://hvacprotech.org/toc/vacpump%20oil.htm

[nike123]

I large system as same as 3000 ton cold store NH3 it take loge time to vacuum it ( unfortunately I have not big one) by my small vacuum , So I use bittzer compressor to vacuum it then after running system
I do Air went action by manual or if I have air purge system by it
My Air compressor specification is D = about 80 mm stork = about 120 and I changed compress Ring
To Teflon graphite ring as same as we have in CO2 compressor and in oil free compressor.
Also I do not know , how I should measure moisture in system , if you have information please inform me .
To cover my this disability I have to change 2 times my Core Drier after running system
Also I change 1 time in ferion system Core drier when I put New system (medium and up system )


I am not familiar with ammonia systems, so I cannot comment this.

[mbc]

thanks about your information
I do not have electronic vacuum meter I will try to get form EU. I have not seen in our country

[nike123]

Then I suggest you to acquire this one:
http://www.inficon.com/download/en/PilotPlus_SS.pdf

Middle East / Africa: Sales & Customer Service: Semiconductor/Vacuum Coating Processes

Please contact the office nearest you or call +1.315.434.1100 for additional information. Residual Gas Analyzers, Leak Detectors, Vacuum Gauges, Valves & Components
Israel
Mark Technologies, Ltd.
Phone: +972.3.534.6822
FAX: +972.3.534.2589
Email: urimark@mark-tec.co.il

Israel - Thin Film
ODEM Scientific Application Ltd.
Phone: +972.8.948.0780
FAX:
Email: ori@odemltd.com

Other Countries
INFICON GmbH
Phone: +49.221.347.41321
FAX: +49.221.347.41478
Email: leakdetection@inficon.com

[goshen]

http://www.supco.com/images/pdfs/2009%20HVAC%20Caralog/2009%20Catalog%20Refrigeration%20chemical%20for%20Web.pdf
try this 2 they are pretty good and much cheaper!! page 68

[nike123]

http://www.supco.com/images/pdfs/2009%20HVAC%20Caralog/2009%20Catalog%20Refrigeration%20chemical%20for%20Web.pdf
try this 2 they are pretty good and much cheaper!! page 68

I have VG64 and I am not happy with his performance.
Sometimes you don't know what is happening and it does not react logically. I clean it regulary with alcohol, but I am not happy with him.
That is why I recommended Inficon because that one is other sensor principle (no thermistor type) and it has filter.
Pirani sensor is known as best for that use.

[goshen]

hi nike point taken i agree just depends on his budget

[mbc]

Nik
I live in Iran and our government has not let us to contact with Israel I have to go to Turkey or Dubai - Thanks

[DEVITG]

Wasted money and time. Write it off, it won't work, whatever effort.

If well done , it will work.

I did it , so I know about it.

[goshen]

http://www.supco.com/images/pdfs/2009%20HVAC%20Caralog/2009%20Catalog%20Refrigeration%20chemical%20for%20Web.pdf
try this 2 they are pretty good and much cheaper!! page 68

so were back to this one good luck mbc!!!:)

[Peter_1]

Wasted money and time. Write it off, it won't work, whatever effort.

I posted some time ago - around 1.5 year ago - the same problem on a pack we installed with several coldrooms on it and even freezers.
You can find my post about this issue here on RE.
There were buckets of water in the system.
The system is still running without any problems so far.
It's possible you see.

[Peter_1]

Purge with nitrogen, place removable filter in suction and liquid and replace as often is needed to remove all moisture.
We had 2 spare filter shells with closed tubes on in- and outlet. We removed the saturated cores, heated those in a microwave for 5 minutes till they had +/- 50°C. We then put those in this spare filter set and vacuumed it with an electronic vacuummeter on it to monitor the drying process (took mostly not longer than 20 minutes)
We didn't need to vacuum this way the whole system, ony the core.
We also removed cores and put those in the shell not heated and vacuumed those and monitored then the vacuum rise after shutting down the pump to evaluate of the moisture content of the core (schematic of Nike)
We installed - I forgot the right numbers - perhaps 30 cores in this system.
And changed finally once again the oil in the compressors.
There are no proven standard methos for such a disasters, you only can do what you thin it's the best to save the system (ours was only 2 years old)

[NoNickName]

The system is still running without any problems so far.
It's possible you see.

So far.
And what about the costs?

[Peter_1]

Anyhow only a small fraction of installing a whole new system of 125.000 Euro

[baycuclaudyu]

Hi all.I have the same problem with centrifugal Mc Quay chiller and I risolve the problem very hard .After u check all leckege with nitrogen put the vacuum pump as longer it need.As example I vacumate 6 month all the sistem .After 2/3 days change the oil in the vacuum pump ,will see the water in the oil pump .If u have patience ,results will caming soon.Is necesary to mounted lickuid dry filter and put the new oil after u finish with vacuum.I use all this steps and chiller (1600 tone)is working after 8 month when i finish repairing.Good luck.

[NoNickName]

wow, long evacuation time!

[goshen]

wow, long evacuation time!
wow!!!!!!!!!!!!!!that is an understatment!
seems like u need a bigger pump!:eek:

[nike123]

wow!!!!!!!!!!!!!!that is an understatment!
seems like u need a bigger pump!:eek:

And proper procedure.
Like flushing, multiple evacuation and dry nitrogen blowing, equipment heating, isolation of parts of circuit etc....
Six month is some kind of record, i suppose. :eek:

[NoNickName]

I'm more and more convinced that recovering a system from water ingress is just a waste of time and money.

[Magoo]

I agree with "nonickname ", in that by the time you do all and sundry clean-up procedures, oil changes , filter changes, you still have a suspect system. Consider all the costs associated material costs, labour costs.
Do your client a favour and rip it out start again with a new system and get new factory warranty as well.

[goshen]

I'm more and more convinced that recovering a system from water ingress is just a waste of time and money.

sorry but i disagree if system is vaccumed well and tested there is no reason for repeated failure,
we have done this in the past and so far havent had any problem ,if u work with the proper tools and procedures u finish the job fast and efficient;)
good luck to us all

[Peter_1]

I'm more and more convinced that recovering a system from water ingress is just a waste of time and money.

Practical field experience learned me and apparently others that it can be done with a very good final result. If you have a pack with 15 cold rooms and some freezers on it which is running 24 hours/day, then there's not much choice left neither. Also, I've done it in the far past several times (chiller, on ships with broken condensers on seawater,..) We even repaired shell and tube condensers on board or in the shop at that time one of Belgiums biggest engineering (included refrigeration) companies (+/- 600 peoples)

[Peter_1]

What convinced you more and more that it is a waste of time? I'm reading just the opposite here.

[NoNickName]

I'm reading not just the opposite, but actually it all ends up blaming somebody else. Salvaging such systems is some sort of russian roulette, everybody say: "if the system is evacuated well", or "if the work is done correctly", "if it has been cleaned properly"... but at the end of the day who know if the "if's" are all properly obeyed to.
I mean, we are all good and trustyworth people, but if it was me, I wouldn't dare recommission a system which was subject to such extensive damage and restoration. What guarantees would I have?
On one thing I agree: for a refrigeration engineer, this is a FATTY work, and no blame on fail.

[goshen]

I'm reading not just the opposite, but actually it all ends up blaming somebody else. Salvaging such systems is some sort of russian roulette, everybody say: "if the system is evacuated well", or "if the work is done correctly", "if it has been cleaned properly"... but at the end of the day who know if the "if's" are all properly obeyed to.
I mean, we are all good and trustyworth people, but if it was me, I wouldn't dare recommission a system which was subject to such extensive damage and restoration. What guarantees would I have?
On one thing I agree: for a refrigeration engineer, this is a FATTY work, and no blame on fail.

hi there ,it isnt a matter of if ,just do it right and it will work!!
our job isnt gambling ,it is only a matter of yes and no,when a unit with a water condenser springs a leek u can either fix it or dump the machine ,usually the customer will pay to fix it ,a new machine is much more expensive!!
we had a quite a few machines with this problem and i can tell u after replacing what needed to be changed and monitoring the unit we have never had repeated failure in these units
u are correct if the damage is over 50-60% of the units cost ,then fixing becomes a questinable issue.:)

[NoNickName]

No, it isn't gambling, but please don't play the game of pretending every refrigeration engineer is a undeflorated virgin.
Just browse this very same forum: there are refrigeration engineers who charge by sight glass and not by subcooling, or don't even know what subcooling is, or even ask for compatibility of HFC with mineral oil...

[Magoo]

NoNickName.
You and I totally concurr.

[lowcool]

be a bugger if a similar fault occured in a short space of time on the same plant after it all has been replaced.strip,flush,dehydrate and evacuate.whats the problem?

[goshen]

big big bugger!!!!

[nana191]

Dear all

I have finish repaired the Hitachi chiller.

I'm going to change oil and refrigerant tomorrow first time.

Thank for all yours ideas.