bitzer screw pack help please

[Mr-Frosty]

the pack is running a chilled production area and had a heat exchanger fitted we attended site to find a hp line ruptured and also found the heat exchanger passing across to the water side. the water has been shut off for 4 weeks and we noticed the ball valve on the water side had ruptured due to the line freezing with water. we removed the heat exchanger and vacced the system out we then re charged with 500kg of r404 to find the system was full of water and we were not getting the sufficient back pressure. we now need to reclaim the system and get rid of the water there are 6 evaps on this system what would the best way to approach this be as i feel the system is very heavily contaminated.

thanks for your help in advance guys its much appreciated.

[mad fridgie]

the pack is running a chilled production area and had a heat exchanger fitted we attended site to find a hp line ruptured and also found the heat exchanger passing across to the water side. the water has been shut off for 4 weeks and we noticed the ball valve on the water side had ruptured due to the line freezing with water. we removed the heat exchanger and vacced the system out we then re charged with 500kg of r404 to find the system was full of water and we were not getting the sufficient back pressure. we now need to reclaim the system and get rid of the water there are 6 evaps on this system what would the best way to approach this be as i feel the system is very heavily contaminated.

thanks for your help in advance guys its much appreciated.

Install drain points at all lowest points (each evap etc), removal of free water.
Get air compressor, cool air resaviour (remove moisture), then Heat the air, then introduce into the system, blowing through the system, leave for a time. Nitrogen and vac.
change oil, filters dries.
Time and Heat, more heat less time!

[Brian_UK]

Interested to know how if the system was full of water you managed to evacuate the system without noticing?

[PRESS]

Hi,

Much as I am interested in knowing the same thing as Brian wants to know I think what you need now are the corrective measures to get your system up and running again. In this case Mad fridgie's method will be an option to seriously consider. To be honest I do not forsee you using the same old moisture contaminated gas and get away with it like that. If you want to simplify things just thouroughly dry the system and induce a fresh charge.

I had a similar problem begining of this year with an old R22 chiller which raptured its tubes when an antifreeze thermostat failed. Believe me the only way out is to dry out the system thoroughly with dry air and dry Nitrogen. Use your moisture indicators correctly before you even think of charging the system again.

Best of chances with this one Bru.

[Magoo]

Suggest everything as per Mad Fridge, and in addition remove the screw compressor and bake in an oven for a week at +80.0 'C under vacuum. Plus invest in a digital vacuum gauge before adding new refrigerant.

[Mr-Frosty]

thank you for your comments guys the system had 3 vac pumps attached for a period of 24 hours and the torr gauge on my vac pump had reached a suitable level that was when we decided the system was fit to be charged. we also thought that due to the water being off for 4 weeks that the possibility of the leak pulling the water in was slim. we noticed the problem when charged with refrigerant because the system stages up and down on pressure through each compressor and unloading valve and we could not get more than 1 compressor to run at 50%.

when recovering the refrigerant could we not run it through filters to the bottles and then back through filters when re charging?

thanks for your comments guys all help is appreciated.

[Magoo]

The refrigerant is not re-usable. Driers will not separate free water, add the chemical reaction in refrigerant with water. Start with fresh charge after clean up.