Install used units... the hell on earth.

[AlexLPD]

https://imgur.com/49823d67-fc72-46b0-904c-498cc4d3ebc9https://imgur.com/49823d67-fc72-46b0-904c-498cc4d3ebc9
https://i.imgur.com/N4YAoca.jpg
So, long story short, A client bought a condenser and two small evaporators (two fans low profile).

:mad:"The seller say this equipment it was working perfectly... yeah rigth...:mad:

https://i.imgur.com/7sReY8L.jpg


So, we install, a single condenser on two evaporators R-22 make leak test and all was good... the next day pull a vacuum and it was good. Charge some refrigerant, all seems to be ok, we leave it and went home, the next day the client call me, the control of the unit has set an alarm, we check for pressure and the compressor was al 4psi on the low side.

Stop the unit retrieve the refrigerant and blame on a TXV on one of the evaps, (wasnt pull down temperature). and surprise surprise when we cut the liquid line, a whole bunch of liquid refrigerant blow out of the pipe... So, we replace the TXV, assembly the hole thing and perform a leak test.

All good to go, charge some refrigerant and went home... the next day, the cold room was not cold... I be dam... check for pressure and 4Psi on low and 120 on High.

At firs tougth It migth be a leak so, I charge some dye and more refrigerant and leave for the weekend, the 4 hours we were there the room was ok... so I call it a day...

Next day, the room was not cold... check the pressure gauge and I have 10 or so PSI on the low side, and some 120PSI on the high side, we look for the leak... no spot, no were, no dye, no oil, no nothing.

So, on this moment, I start to be really really mad, Its is not possible to leak this much and leave no mark what so ever.

Retrieve the refrigerant, cut the pipes on the compressor and bout evaporators, so I improvise a pressure device to inject thinner (I know...) so, flush one evap, and this thing come from it,

https://i.imgur.com/ebhp8FX.jpg

Flush the other evap... and this came out...


https://i.imgur.com/q2G1LOE.jpg
I cant see to understand... how it is possible the dye is in only one of it...
The contaminants where ever they are, one goes above the solvent and other goes below!!!

https://i.imgur.com/LOe7Ueq.jpg

So, dye and refrigerant were stuck on some part of the refrigeration system, flush the evaps, and the orifices of the txv, leave overnight, flush with some air, then n2, weld all, pull a vacuum and charge some refrigerant...

https://i.imgur.com/huLjP2E.jpg

it works like a champ.
So, lesson learned, always charge for the flush, before install, and also, clearly state this kind of job, will be added to the charge.

PS. the client pays for it, he understand the problem came with the units.


Kind regards.
-Alex.

[martinw58]

flushing with air can put moisture in the system

[al]

At least you stuck with it to get it working, I hate installing customer supplied gear.

[AlexLPD]

Yes, Im aware of that detail.
But, my main priority, it was to make the machine to work.

Thanks.
-Alex.

[AlexLPD]

For some time I was so sick, of this, I cant figure it out.
-Alex.

[AlexLPD]

Well client call me after a week or so, the coldroom dont go below 7C...
A quick revision and we got a very weird problem, low pressure on HIGH and low pressure on LOW. So, I migth think this is a clog... I recover the refrigerant and wash the TXV orifice;
https://i.imgur.com/BozmjRa.jpg

No bad so far, still I retrive the 4.2Kg of refrigerant on the system, so I know its not leaking, I remove the filter drier and reverse wash it with some thinner;

https://i.imgur.com/4OIxKvQ.jpg

On the left the first wash, on the rigth the second wash...
The last week wash was this, has know settle down and show something like dirt;
https://i.imgur.com/D3bnoOO.jpg

So, more interesting stuff to happen;
I close the system and pull a vaccum on it ( the last time it was pulled good), but this time I cant get the vaccumeter to go below 2000, and the new oil in the pump turn in to this;

https://i.imgur.com/c7OMff3g.jpg

I guess there is a huge amount of moist on the system, and the clear phase in the bottom of the conteiner is water.

So, after two filter dryers and 2 vaccum oil changues, the system is charged and ready to go, still works fine. But now, an OEM TXV that was on one of the Evap is not closing so, I will need to changue it ...

Small story;
Clients supply equiments its a sure headache.

-Alex-

[chemi-cool]

Why not flush the system with nitrogen? It will absorb the moisture and clean the pipe work.

Another thought is to replace that unit completely and start fresh.
It will cost your client less.

[Tayters]

Hi Alex.

Low pressure on high and high pressure on low, is that what you meant to type?
If so could be the compressor not pumping correctly. Do a pump down test to confirm.

Cheers,
Andy.

[AlexLPD]

I will do so, tomorrow will come back with more information about this stuff.

Thanks.

_alex.

[AlexLPD]

Well, this system has not yet to amaze me...
I have to change the other TXV, since the old one dont work. log story short;
Nitrogen high pressure test, pull vaccum, chargue refrigerant, star the unit... bad compressor.
It was not burned, just move like it was in the start, but nothing.
So..
Retrieve the refrigerant, intall another compressor, changue the liquid filter, and install a suction filter, high pressure test, pull a vaccum, charge the refrigerant...
System pulls perfectly.

Know on the economic subject, I have still to charge the client for all this services, so, I wish me luck.

-Alex.

[RANGER1]

Well, this system has not yet to amaze me...
I have to change the other TXV, since the old one dont work. log story short;
Nitrogen high pressure test, pull vaccum, chargue refrigerant, star the unit... bad compressor.
It was not burned, just move like it was in the start, but nothing.
So..
Retrieve the refrigerant, intall another compressor, changue the liquid filter, and install a suction filter, high pressure test, pull a vaccum, charge the refrigerant...
System pulls perfectly.

Know on the economic subject, I have still to charge the client for all this services, so, I wish me luck.

-Alex.

Alex,
As soon as you hopefully fix this problem system, you have no leverage for him to pay.
I would be asking for some money before you install new compressor.
Cry poor before he does.

[AlexLPD]

Alex,
As soon as you hopefully fix this problem system, you have no leverage for him to pay.
I would be asking for some money before you install new compressor.
Cry poor before he does.

Hi and thanks for the advice, in deed.
I changue the compressor and the two TXV on the system, the cold is delightful the client has no more complaints, over the service, the cost is another subjet.

He pays me the last bill, and want to come together with the person who sell the unit, for "guarantee"..
regardless I spoke to him, and he was on the agreement to pay me if the seller dont respond on this matter.

Thanks to you all.
-Alex.