High Intercooler level

[Markridgway]

We are experiencing high intercooler level when the system has been stood idol over the week end, the compressors wont start up with the value this high. Can someone explain why this is happening as we have shut various valves of a weekend and it is still happening

[Segei]

Can you give us more information? Is it ammonia refrigerant? Does intercooler has pump?

[Markridgway]

Yes its ammonia and the only pump is the the liquid pump

[weagle]

I think you might have a leaking check valve on that pump and the liquid may be filling up the vessel. Did u inspect the liquid make up valve feeding the vessel? That may leak and fill the vessel as well..

[RANGER1]

Need more detailed information!
Does the inter-cooler have a liquid pump on it, as its not 100% clear.

Liquid may migrate from rooms or whatever is connected to it when shut down & warmed up.
Also ammonia will expand when warm, showing higher level in vessels.
Can or does liquid pump start before compressor so as to circulate ammonia back into evaporators?
Is it a new problem?

[RANGER1]

If it's a critical charged system there is a possibility it's overcharged.

[Grizzly]

I like following Ranger, You ask all the correct Questions my friend.
Mark.
You obviously given your series of questions have lost control of your system.
Here is a guess.
Your surge drum control has been lost due say to a malfunctioning level control?
Your liquid makeup line solenoid valve to the inter cooler is Passing.
Which in itself would not always be an issue, but if the level in the surge drum was artificially high the system charge would look for a new home!
It's just possible that your liquid could then migrate to the inter cooler.
To identify one problem is hard, when you have 2 or more then you have to go back to basics and start at the beginning.

OH! by the way if you do have an actual high inter cooler high level on start-up?
Then that could be the reason why you pump is cavitating.

A classic case of the charge gone walk about!

I have seen many systems loose control, simply because the oil in the system is in the wrong place.
When was the last time you oil drained, does the oil separator have a bleed line back to the level column?
What is the oil level in the oil separator?
There are loads of questions, rather than trying to control an efficient piece of kit like the comp / oil pump.

Step back and try and confirm where you are actually loosing control.
Ask where is the difference in settings / levels from the norm.
Most of all let us know how you get on, so we all can learn from this!
good luck Grizzly.

[Magoo]

Hi Mark.
Is your system a compounded two stage with intermediate intercooler de-super heater vessel ? just want to clarify. If that is the case what level make-up do you have on intermediate inter-cooler ? A level float system or similar.
As per all the above posters some more detail would be cool. Cheers magoo

[Markridgway]

Thanks Grizzly..I will keep you informed

[Grizzly]

Thanks Grizzly..I will keep you informed
Thanks for the valued response Mark, but don't forget other as well as myself have contributed!

Grizzly

[Markridgway]

Yes you are quite right I would like to thank all who have commented on the issues i am experiencing. Sorry I have not asked before now.
The site and help provided is a good troubleshooting tool to have.
I am far from being a refrigeration engineer but since we dont have one on site anymore and I have to start all the compressors of a night you help is going to be invaluble
thanks again chaps

[Segei]

Try to pump out (lower the level) intercooler before switching off the system.