water in system

[coolhibby1875]

hi all, i have a blast chiller with some water in the sytem, i have done the normall stuff, decant the gas, change drier 3 times vacumed over night 3 times, and have broken each vac with nitrogen, i now have it on a new drier and expansion valve and on another vac overnight tonight, so when i come in 2morrow i will weigh in fresh refrigerant and run it up, question is if this doesnt work should i give up or does anyone have any tips on how to rid the system of water / moisture?:confused:

[sedgy]

hi coolhibby,
yes its very annoying , have you ever tryed ofn warmed up with a gas heater blower? get the ofn bottle as hot as you can < theres no liquid in the ofn<110cand blast it through the system get the system as hot as you can vac out with the heater blowing onto any bare metal , comp, condencer, so any water will boil off ,
best of luck, sedgy,

[james10]

you also need to be carefull with the low ambients we are having, as water in the system could have frozen and pulling a vac to quickly can cause the ice to remain in the system i would use a vac pump with a gas ballast function and vac with the ballast open overnight then pull a deep vac with the ballast closed then do a rise test with as much heat going on to the system as possible let us know how you get on
Best Regards
James

[monkey spanners]

If the system is really wet, change the oil at the same time as the drier.
I had a maneurop compressor that was so full of water that its oil poured out the suction connection! that i dried out this way, had a big two core drier shell in the suction and just changed them and the oil every day for a week.

[G Cook]

We recently had a small water chiller that froze up, the heat exchanger burst and filled the system with water.

As there was lots of moisture in the system we removed the compressor and tipped the water and oil (mostly water) out. The heat exchanger was removed and the pipes were joined with a piece of pipe. We then blew nitrogen through the pipe work and the removed compressor. The compressor and chiller were then triple vacced (and heated) until the moisture was removed.

Once they were both dried fresh oil was added to the compressor and it was re-fitted to the chiller. A larger filter was fitted, new oriface and new heat exchanger, then pressure test and vacced again.

It seems to be working.

[Grizzly]

Hi Coolhibby.
If the water contamination was bad?
You could make a cold pot which is what our lads use on marine.
The navy have a habit of freezing and splitting tubes.
The cold pot is a refrigerated coil within a pot which is inline with the system and vac pump.
As the vacuum sucs out the damp vapour from the system the cold pot draws the moisture/ water out of the Vapour as its passed over the internal refrigerated coil within the pot.
Periodic isolation of the pot defrosting of the ice covered coil within it.
The whole thing is then reassembled and the process repeated.
But it does reduce greatly the Vacuum pump oil contamination.
All that effort is more viable on large systems though!
Grizzly

[tonyelian]

hi
i am with what monkey said & i would like to add that u have to seperate evaporator
and condenser blew each one alone with nitrogen take every part out clean them and change motor oil twice let it run for 20 minutes for the first change then empty it fill it again it is a hard job but it works

[coolhibby1875]

cheers guys, will see how goes tomorrow, will let you know!!

[coolhibby1875]

well after fitting new drier and valve AGAIN and being on vac for 36 hours, ran for 2 mins and choked again:(

[Emmett]

We had similar situation and it took a month to dry the system out. We used dry nitrogen purge for hours on end and vac and repeat until vacuum held, changed driers and oil multiple times we have not had any problems with unit for 8 months now. Are you sure you have eliminated the source of the water?

[sedgy]

hey coolhibby, this is when the job tests you , we have all been there , lets look at the job ?
where did the water come in? = is this fixed?
the water has settled some where= find it, you may have to strip down the system , compressor, evaporater, cond, unit, pipework , blow out each individual part< is it posible to seal off each individual part and vac out same leaving them with ofn in them untill you reassemble< its going to take time, you cannot rush it
heat + ofn . all the best , sedgy,

[Gary]

I have found that vacuum does little for water in a system. Changing driers and compressor oil seems to be the only answer.

[paul_h]

Heat?
pumping metho or another liquid designed to flush systems through to flush the indoor?
For the outdoor, as said, just oil and drier changes.
A vacuum removes moisture, but won't remove masses of water

[mad fridgie]

For large amount of water and/or when areas are cold you need to introduce a dry hot gas (air is OK)
I Like to compressor air to about 10Bar cool it as cold as I can (condensate the water out) expand to 2 bar, heat up to about 60C, then introduce into the system (discharge), open all valves, vent from the suction.
(comp is closed off, oil is changed,)
If parts are in a very cold area (evap in a running store) I cover with blankets to keep the heat in, may even run elements, but you do need to keep an eye on this, do not want a fire!

[coolhibby1875]

hi guy's the chiller is an integral on a medium sized blast chiller, source of water is gone (fractured pipe on evap),the water i thinkis in whole system now, i will keep at it as the unit is un the workshop and i have plenty time on my hands :)

[mad fridgie]

hi guy's the chiller is an integral on a medium sized blast chiller, source of water is gone (fractured pipe on evap),the water i thinkis in whole system now, i will keep at it as the unit is un the workshop and i have plenty time on my hands :)
Cover with a blanket (make a tent), but a small fan heater inside the tent, and leave on vac. But a stat on the heater, just so you do not have a fire.
Higher the temp , the shorter the vac time and will be easier to see if all the moisture is gone.

[coolhibby1875]

removed compressor and drained oil, whilst comressor was removed i welded in a shreader onto the open end of the discharge line, removed the orrifce from the exp valve then blew a large nitrogen bottle up through the discharge and out the suction, i refilled the compressor with new oil, fitted back the orrifice and after a quick vac its purring like a kitten, :)

[charlie patt]

i would change oil and heavily purge with nitro if unit has a oil sep or a acumulator always check its not contaminated fit a heavy dessicant drier and a suction drier leave nitro in overnight and when vacing use a good cfm pump and when vacing use a heater to boil of water use a torr gauge and get a suitable vac if it has a oil sep it will be full of water be lucky ta charlie

[sedgy]

hi all , so we are coming round to heating up the system to get rid of the moister or water¿ has anyone tryed heating up a bottle of ofn blasting it through the system yet?
yes prestip`the sysem pour out the water great, but without heat how you gone get rid of the water?

[monkey spanners]

hi all , so we are coming round to heating up the system to get rid of the moister or water¿ has anyone tryed heating up a bottle of ofn blasting it through the system yet?
yes prestip`the sysem pour out the water great, but without heat how you gone get rid of the water?

Last one i did, cut system into sections, remove txvs etc, connect ofn bottle to one end, fit oversized lever ball valve (plumbing type with extension pipe) to other end of system, puff system up to max safe pressure, shut ofn bottle, ppe, open ball valve, water comes out, repeat till all gone.

[alan wolf]

Hello

My recommendation is obtain and fit an absolute vacuum gauge and find out what vac you actually have.

if system is still wet you will not get vac down. a large pump or you cant heat system enough the moisture freezes up.

Get some saturation tables for water to give you an idea of evaporating temp of water.

I have just seen a large chiller evacuated for 6 weeks to get water out after a condenser tube failed.

was down to 3 torr.

Alan

[Fri3Oil System]

When you pull a vaccuum, the water that remains below the oil in the syphons, won't evaporate easily.
One of our clients in Spain didn't believe our system could take out all the water from a system. So, they wanted a proof of it, and their great idea was to sink an evaporator in a swimming pool! we took all the water during that training... it took several hours anyway. At least, the client got convinced.

Regards,

Nando.