Cleaning of Ammonia system after installation

[skhan855]

Hi

I am finishing my installation of Kirloskar compressors into system, we have done lot of welding works including self build of new condenser and repairs of new one.

I checked with my fellow installers and they advised that Kirloskar compressors have safety devices within compressors that do not tolerate dust / welding or other contaminated particles and would result in tripping of system.

Please suggest how should I clean my system before trials, I have one spare used compressor, should I pump air into system to get rid of particles? or charging Nitrogen would help?

Regards
Salman

[Kenneth199]

What type of welding has been used?

[Magoo]

inside the suction strainer that you have already installed fit a suction sock, A heavy cotton material that catches fine particles, check it weekly and clean then remove once the system has cleaned up. Change oil filters regularly, both will stop junk entering compressor.

[skhan855]

@ Kenneth199
It's both electric and Gas welding.

@Magoo, your idea is very logical, meaning creating sock over filter, if I am correct?

What about installing additional filter at suction line before strainer? this will create 2 filters to avoid junk?

[RANGER1]

If you have a new installation vessels which are pressurised with air or nitrogen, the pressure can be used to blow foreign participles out by removing valve bonnets etc.
Compressed air blowing through pipes, vacuum cleaner.
Not a big problem if pie kept clean on install & Tig welding.
It's usually liquid line strainers that cause the most grief if pipes dirty or rusty.
when installing valves the body of valve obviously should be cleaned thoroughly.
A strainer before a strainer seems a bit of overkill & as Magoo suggests a Calico temporary sock with pure cotton stitching.
Maybe compressor manufacturer can supply as other manufacturers like Vilter & Sabroe do.

[skhan855]

Hi

So this means that only possible solution is to pump air or nitrogen to remove foreign particles.
Secondly putting socks on strainer could prevent particles entering into compressor

Can someone suggest how much nitrogen would be require to fill in condensers / system. I know its a il-logical question as this would depend on system to system and size of system, but I need a rough idea to know a rough volume.

[Magoo]

The suction sock is fitted inside existing suction strainer. Also sporlan supply liquid filiter driers for ammonia , use standard RC4864 or RC 10098 direr cores, recommend twin parallel with pump out valves, so you can change cores without interruption to operation good for filtration and moisture removal.

[RANGER1]

Hi

So this means that only possible solution is to pump air or nitrogen to remove foreign particles.
Secondly putting socks on strainer could prevent particles entering into compressor

Can someone suggest how much nitrogen would be require to fill in condensers / system. I know its a il-logical question as this would depend on system to system and size of system, but I need a rough idea to know a rough volume.

I think you need large volume area like liquid reciever pressurised.
From that point if you remove valve bonnets on isolating valve on inlet to condenser, you can blow back through it by opening isolating valve on condenser liquid drain.
Same with liquid line.
You Have to be careful not to damage valve seats if high velocity gas passing over them impregnating particles.
Not knowing what size bottles of nitrogen suggest 6 "G" size bottles or a pak of 12, doesn't cost that much (in our part of the world).
Entire System is usually pressure tested for leaks & strength test using nitrogen anyway.

Is is it a complete new system?

If there is some place to hold volume of pressure on suction side of compressor, use that to blow compressor suction line clear.
You may only need pressure below 1000 kpa for this.
You can you use compressed air if humidity not to high, your choice, nitrogen best.

[RANGER1]

The suction sock is fitted inside existing suction strainer. Also sporlan supply liquid filiter driers for ammonia , use standard RC4864 or RC 10098 direr cores, recommend twin parallel with pump out valves, so you can change cores without interruption to operation good for filtration and moisture removal.

Is this a standard thing Magoo, never seen it used on ammonia.

[Magoo]

Hi Ranger.
Yes sporlan do supply standard drier cases with steel stubs for ammonia up to two inch stubs and the cores as stated do the job.
Check the sporlan supplier, not too many people use them unfortunately.
I inherited a relocated system that was a rush job and liquid ammonia was black with mill scale from pipe work. Started to effect everything in system, every solenoid valve, control valve. Fitted twin parallel filters with bypass valves, gauges and pump out valves, lived there for a week changing cores initially, but now system and ammonia is crystal clear/ normal. No more valve/ control valve issues. Took several cartons of core filters to clean up system. So after clean up now a larger service provider looks after total system and I got tipped out, bugger. They change cores annually only no moisture and oil problems, oil drains normal.

[Magoo]

Hi Ranger again
Check sporlan cattle dog Bulletin 40-10 page 23 two inch connections up to 450 tons refrig duty. hard copy is old like me so could have changed.
What ever a good clean up idea for systems .
magoo

[skhan855]

Hi

Thanks for all information, will keep you posted.

[Glenn Moore]

Hi Magoo/Ranger
For your info Danfoss a few years back introduced an Ammonia drier for the DCR range of driers, and also a strainer basket. The sales for these were very poor as virtually no one fits driers in NH3 systems. I sold a number of these driers to customers to clean up the LT pumped side of a number of systems where the ammonia was heavily contaminated with water causing the PM control valves to rust and seize the piston rings preventing the valves working.
As Magoo says the system takes ages to dry and clean the system but they did work very well. They stopped doing the strainer filter which had a cotton base, but still do the polyester version for HFC's. They no longer promote the sales of driers for ammonia but I know a number of my old customers still use the DM cores in NH3 systems to clean up dirty systems. It does take a number of core changes to clean a system , and the drier shell becomes warm to the touch as there is some kind of chemical reaction during the process, but when needs must it may get you out of trouble.