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jalber
20-05-2008, 09:13 PM
I have a Chester Jensen Ice Builder (100 Ton) and every 4 days or so the outlet of the surge drum seems to get plugged with something. I have drained the oil pot and the problem is still happening.

To get the ammonia flowing again I turn off the liquid feed and heat the outlet pipe, in 1-2 hours of heating the pipe it opens up.

Any thoughts or experiences would help out.

Thanks

US Iceman
20-05-2008, 09:58 PM
Are you heating a pressure regulator or the piece of pipe off of the top of the surge drum?

Grizzly
20-05-2008, 11:32 PM
Agree with Iceman also
When you say you are oil draining. How much Oil are you getting out?
And how does that correspond to how much is being added?
I don't wish to be rude but how slowly are you Oil Draining. Old Stinkies will understand what I am thinking.
Cheers Grizzly

US Iceman
21-05-2008, 01:28 AM
I believe there is a lot more to this than we know right now Grizzly.

jalber,

When you come back and read the replies can you provide some operating conditions please?

Suction pressure at compressor....

Pressure setting of back-pressure regulator (if installed)

Is the liquid level control to the surge drum by float switches controlling a liquid solenoid upstream of a hand expansion valve?

What is the water temperature in the ice builder?

Does it have ice on the coil when this problem occurs?

Any little detail you can provide helps us to help you.;)

jalber
21-05-2008, 02:41 PM
Thanks for the replies, here is some more info.

20 psig compressor suction
bpr is wide open 22 psig
float switch controlling a liquid solenoid
hand expansion wide open
ice builder water temp 32-34 normal 37-45 when problem occurs
No ice on coil when problem occurs
I am heating the outlet pipe of the surge drum (drop leg)

Normally the outlet pipe and the 2 return pipes are iced over. When the problem occurs the outlet pipe is frosted and the return pipes are bare. I removed the insulation from the surge drum because it was no good. now when the problem occurs the frost on the surge drum begins to melt.

At first I thought a liquid supply to the surge drum problem. Looking at it further the float durning normal operation has about 70-80% on time, when the problem occurs it is 20-30% on time.

If you want more info just let me know.

Thanks for the time.

John

jalber
21-05-2008, 02:58 PM
I got about 3 gallons oil total out of oil pot. I isloated the oil pot let most of the liquid boil off and then drained the oil.

jalber
21-05-2008, 02:59 PM
By the way it is a pumped liquid system, not HPL.

Camille
21-05-2008, 04:37 PM
Can you draw how the Chester Jensen is is piped to the system, type of valves on the dry suction , liquid supply, operating liquid level, design criteria, we do install lots of these units, flooded and liquid recirculation and I might be able to help once we see the as built sketch

jalber
21-05-2008, 07:09 PM
Here is a PDF of the install.

Grizzly
21-05-2008, 10:22 PM
Jalber.
Thanks for the details so far, a good effort.
Sadly this one has me confused.
My first though was Oil Logging but now I am trying to work out Where the extra heat .
Is coming from within the freeze cycle.
Throwing a complete curve ball!
When the temp/ pressures rise what is the temperature of the water supply.

Sorry I seem to have more questions than answers at present.

By the way how does the 3 gallon of oil stack up against how much is being added to the system?

Sorry I can't be more helpful.
Grizzly

Tycho
21-05-2008, 10:49 PM
is it a stand alone system, or is it piped into another system?

zolimer
22-05-2008, 01:59 AM
"ice builder water temp 32-34 normal 37-45 when problem occurs"
I may be wrong here, but it sounds to me like your outlet header is going to a plate chiller, you are getting clogged and the temperature on the outlet side of the plate chiller is rising! please elaborate!

RANGER1
22-05-2008, 01:11 PM
Could the level control float have oil in its line from drop leg point to bottom entry of float.From the drawing it is a horizontal 1/2" line,but is it horizontal ?
If line slightly falls towards float it could fill with oil causing sluggish operation.This line should fall towards drop leg (the more the better).Does the liquid reciever level increase when no ice on surge drum/leg?
Is there ice on float valve and bottom inlet line when it works ok?
Suggest try to clear float 1/2" lines and see if it improves.looks like it is pumping out and stalls thermosyphon.

US Iceman
22-05-2008, 05:10 PM
I've been watching this the last few days waiting for others to comment and ask questions to see what happens...

It's certainly a strange one for sure.



hand expansion wide open


Now that's unusual. I can't imagine why you would have the hand expansion valve wide open unless the the valve was originally sized for high pressure liquid feed and then converted to pumped liquid. The lower differential pressure (from liquid feed supply to evaporating) would require something like this, but still.... it's unusual to see this.



ice builder water temp 32-34 normal 37-45 when problem occurs
No ice on coil when problem occurs
............

Normally the outlet pipe and the 2 return pipes are iced over. When the problem occurs the outlet pipe is frosted and the return pipes are bare.
............
now when the problem occurs the frost on the surge drum begins to melt.


This indicates the problem occurs after the ice has melted off. If the water temperature is reaching 45°F, there is still some load on the system connected to the ice bank.

The frost disappearing on the surge drum also indicates the evaporating temperature is rising, which would make me think there is liquid in the coil and surge drum but since the evaporating pressure has increased the saturation temperature of the liquid is now above 32° (0°C).

Or, the frost could disappear if no liquid is present to cause the frost to form even if the suction pressure is low enough.




I removed the insulation from the surge drum because it was no good.


Don't forget to replace it after you clean and re-paint the surge drum. If there is rust on the surge drum (and I'm sure there is) you could use some of the rust converter paint. This will convert the rust into a hard coating and stop the surface corrosion.

Then paint the surge drum and piping, then re-insulate it very well. And for goodness sakes, please use a good vapor barrier and jacket on the insulation to prevent this from occurring again (or to drastically slow down when you would have to repeat this process).



At first I thought a liquid supply to the surge drum problem. Looking at it further the float during normal operation has about 70-80% on time, when the problem occurs it is 20-30% on time.


I think you still have some oil contained in the ice bank coil or surge drum or float switches. If you are having to heat the drop leg off of the surge drum it could only be oil that would cause this. And, for this to happen to this degree the ice builder coil would have to have a lot of oil in in.

Last question....
How often has the oil been drained from the oil pot and how much is being drained each time it is done?

jalber
23-05-2008, 05:22 PM
Yes, the expansion valve was origionally sized for high pressure liquid supply.


I think you still have some oil contained in the ice bank coil or surge drum or float switches. If you are having to heat the drop leg off of the surge drum it could only be oil that would cause this. And, for this to happen to this degree the ice builder coil would have to have a lot of oil in in.

Last question....
How often has the oil been drained from the oil pot and how much is being drained each time it is done?

The ice builder was bought at an auction about 2 years ago. I do not know if it was oil free when it was installed. Over the last 1.5 years the oil pot had been valved off for some reason. Over the last 6 months or so approximately 5 gallons of oil has been removed from the oil pot. The last time it was drained was 3 weeks ago and he got 3 gallons. I drained it 2 days ago and again today and got maybe a quart total.

To trap the oil I have the feed from the icebuilder and the relief to the surge drum both open. I believe that there is liquid circulation from the ice builder through the oil pot relief to the surge drum, because when I close the feed valve from the icebuilder the frost on the pipes immediatly begins to melt-- even though there is a significant amount of liquid in the pot at 20psig. Is this normal??

I had assumed it was oil, but I am puzzled that it is not showing up in the oilpot. I am going to check the float later on today.


Thanks for the time.

John

US Iceman
23-05-2008, 09:04 PM
I believe that there is liquid circulation from the ice builder through the oil pot relief to the surge drum, because when I close the feed valve from the ice builder the frost on the pipes immediately begins to melt-- even though there is a significant amount of liquid in the pot at 20psig. Is this normal??


The oil drain from the surge drum (or the drop leg) should be open all of the time (except when you get ready to distill the oil off and drain the oil pot).

The vent line from the oil back up to the surge drum (above the liquid level) should also be open all of the time (except as noted above).

It's normal to see frost on the oil pot since it will be full of liquid. As the oil level rises in the oil pot you usually see the frost disappear where the oil level is in the oil pot.

The underlined comment above bothers me though. Are you describing the feed valve to the surge drum or the valve draining oil into the oil pot. Because... if you are closing the feed valve (liquid feed to the surge drum) and the frost disappears that quickly the surge drum is not getting a sufficient supply of liquid.

In which case, this becomes a different issue related to your main concern.

RANGER1
24-05-2008, 01:13 AM
It would also be interesting what oil pot drain point is connected to.
Surge drum or bottom of drop leg in tank?Normally and by picture supplied ,oil drain line is on bottom of coil and piped up to top of tank .Pressure pushes oil up when draining ,to top of tank where an oil drain valve is suitably mounted.You normally have to drain it slowly otherwise ammonia will push past oil in line and you may think its empty .Unless oil drain comes directly out wall into oil pot, which gravity feeds pot on floor ?
Basically oil must be drained from bottom of ice tank,either from drop leg or header on bottom of coil.

Camille
26-05-2008, 05:40 PM
few comments
1- that is a lot of oil to have, 3 gallons, and I am wondering about the system design, why so much carry oil , do you have reciprocating machines , and if you do , do you have a high effciciency oil separators on the machines, check the source
2- where the high pressure liquid feed to the surge is tapped to at the system, hopeuffly is not from the bottom of the receiver,
3- do you have the right quality of oil in the system, is the oil congeling, is it black in color
4- do you have water in the ammonia, could you send a sample to the lab for testing the quality of the ammonia

issues aside
a- do you have normal liquid feed to the surge drum, whay the hand expansion valve is wide open,
b- does the float level operating switch bottom connection slopes to surge drum liquid outlet

Regards

Camille

jalber
28-05-2008, 02:50 PM
few comments
1- that is a lot of oil to have, 3 gallons, and I am wondering about the system design, why so much carry oil , do you have reciprocating machines , and if you do , do you have a high effciciency oil separators on the machines, check the source
2- where the high pressure liquid feed to the surge is tapped to at the system, hopeuffly is not from the bottom of the receiver,
3- do you have the right quality of oil in the system, is the oil congeling, is it black in color
4- do you have water in the ammonia, could you send a sample to the lab for testing the quality of the ammonia

issues aside
a- do you have normal liquid feed to the surge drum, whay the hand expansion valve is wide open,
b- does the float level operating switch bottom connection slopes to surge drum liquid outlet

Regards

Camille
1. Yes we have a recip with an old oil seperator, I highly doubt it is "High Efficiency"

2. When the surge drum was origionally installed it was HPL, but now it is supplied with pumped liquid.

3. Yes, the oil was black. We use Frick #3 oil.

4. I am curios about water infiltration. I don't have a lab here capable of testing that. Any recommendations?

a. The expansion valve is wide open because it was origionally designed for HPL and we are using pumped liquid.

b. Yes the float slopes correctly.

The oil pot is connected on top of the icebuilder, relying on pressure not gravity to force the oil up.


John

RANGER1
28-05-2008, 10:55 PM
For item 4 you dont always need a lab.
Just close liqid supply,pump out coils.You can kill 2 birds by then trying to drain whats in coils ie.dead ammonia if its there and oil if its there.Sometimes leaks may have occured in coil and if/when its pumped out water can get leak into system.Also in your case the unit was s/hand ,so you may not know all its history.
When its pumped down and warm whatever is left is in coils you dont want (oil/dead ammonia) .
The dead ammonia will come out like water and not boil off .Also any oil may be easier to drain because its warmer and there is no liquid pushing past ammonia when draining.

mazbut
31-05-2008, 11:45 PM
It appears your whole surge drum is clogged upto to the neck where the suction pipe runs back to compressor! In that case you will have to check how long does it take for the ''back'' or frost to appear on the suction pipe? If it appears soon you will have to get your surge drum cleaned completely ,,,,
It also shows that your compressors have weak oil rings and need replacement for the quantity of oil resting daily in the surge drum shows your compressors are in poor shape and need rings be replaced.

Apart from heatin there is no other way to get out the 'sludge'' from the surge vessel,,,,once I had to use a blow torch to heat the entire base of the drum (ofcourse you have to take all the necessary precautions before you do that ,,,such as completely vacuum the vessel and cut it off from the systme for a while until it shows some manners 1)