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ctscasemod
09-09-2010, 12:39 PM
Hi Guys,
I'm searching a way of easily recovering old refrigerant like R12 or R22 from old systems, however I don't have a recovering unit. I do it with the equipment compressor, but I can't get all of it, maybe just 2/3.
I was wondering, since I have a 1/4HP vacuum pump if it would be possible to adapt the exaust of it to a bottle of refrigerant.

I thought using an old compressor, but probably the oil on it would mess up with the oil on the refrigerant. Anyone has some idea about this?

Thanks, Carlos

sedgy
09-09-2010, 04:19 PM
hi carlos, you could use a spair condencing unit < if you have one< by the way its good to see young engineers trying to get things right
all the best sedgy,

chemi-cool
09-09-2010, 04:22 PM
In recovery units, the compressor is special one that can handle liquid.
Its oil free and have an oil separator.
You cant do it properly with short cuts.

FaultCode
09-09-2010, 05:00 PM
Surely if you are recovering old refrigerants like R12 and R22 for disposal then you should be using the proper equipment.

If you need to recover the last drops you could use an empty recovery cylinder that has been evacuated and use that to draw out the last bits.

monkey spanners
09-09-2010, 05:08 PM
Hi Guys,
I'm searching a way of easily recovering old refrigerant like R12 or R22 from old systems, however I don't have a recovering unit. I do it with the equipment compressor, but I can't get all of it, maybe just 2/3.
I was wondering, since I have a 1/4HP vacuum pump if it would be possible to adapt the exaust of it to a bottle of refrigerant.

I thought using an old compressor, but probably the oil on it would mess up with the oil on the refrigerant. Anyone has some idea about this?

Thanks, Carlos

A vac pump is not designed for pressure, its likely to go off like a grenade if you try and make it pump refrigerant.
You could use an old compressor or condensing unit, with a suitable high pressure switch wired in and some shut off valves etc but a propper recovery machine would be best for the job.

ctscasemod
10-09-2010, 01:48 AM
I use an old receiver to slow down the refrigerant, so most of the oil gets stuck there as there isn't enough flow to carry it.

I do recovers, not for disposal but for reuse and because I want to think my kids will have a place to live some years later, not an ozone depleted planet!

I cant get 1Kg of refrigerant with a evacuated bottle!Although I use R290 as a direct replacement for R22 and R600 with modifications on the Expansion valve for R134 and R12, there are times were I can't use flammable refrigerants.

What do you mean with an old condensing unit?

Peter_1
10-09-2010, 06:30 AM
In recovery units, the compressor is special one that can handle liquid.

I used now at least 6 different recovery units but I never seen one where the compressor could handle liquid Chemi.
What I have seen is at least 10 broken compressors due to liquid slugging
There is always a special valve where the liquid passes first a restrictor in all different ways.
He can pass the liquid first through a capillary or throttle the valve on your manifold and make a restriction.
The fact that you will use it only for mineral filled system, go for and old condensing unit and it will go much faster then your recovery unit.

Peter_1
10-09-2010, 06:31 AM
What do you mean with an old condensing unit?
Compressor, condenser and receiver, a whole unit

chemi-cool
10-09-2010, 08:13 AM
This is my recovery machine.
It handles liquid great.
As a matter of fact, only yesterday I have emptied a 22 KG liquid into a bottle, replaced compressor and recharged.

http://www.mastercool.com/pages/recovery.html

Peter_1
10-09-2010, 08:36 AM
I have 3 Mastercools in school as well (and one for my own) but the blue button has a special position 'liquid' and there it is passing inside the unit a restrictor, this because the compressor inside the unit can't handle the liquid.

In fact, there isn't such a thing as a compressor which can handle full liquid.

Connect it once to pure liquid and turn the knob to gas and start your machine. The resettable breaker will trip.

Pure legally seen, this machine is not allowed in Europe because the machine only starts when there's pressure on the inlet (you can't override this function) and the machine must be able to achieve 0.3 bar aboslute.

Peter_1
10-09-2010, 08:39 AM
Interesting question relating to this problem and I bet many will make mistakes with this...you recovered R134a on your last job and your next job is recovering R22 or R404a. Or you recovery unit was in you shop for some months
What will you do on this next job and how will you do it?

chemi-cool
10-09-2010, 12:15 PM
I vacuume the unit and purge the oil separator.

With a vacuume pump ofcourse.

Tony
10-09-2010, 12:18 PM
Hi Peter_1,

get a recovery machine which self purges, then you don't have the problem

ctscasemod
10-09-2010, 03:14 PM
Compressor, condenser and receiver, a whole unit

Do you mean the outside unit of an air conditioner!? Or are you referring to the condenser (radiator)?? :confused:

ctscasemod
10-09-2010, 03:16 PM
I used now at least 6 different recovery units but I never seen one where the compressor could handle liquid Chemi.
What I have seen is at least 10 broken compressors due to liquid slugging
There is always a special valve where the liquid passes first a restrictor in all different ways.
He can pass the liquid first through a capillary or throttle the valve on your manifold and make a restriction.
The fact that you will use it only for mineral filled system, go for and old condensing unit and it will go much faster then your recovery unit.

It will not hande liquid. As you said, a capilary tube, an old receiver as expansion device with some kind of condenser maybe. Only vapor to the low side of the compressor. Thanks

nike123
10-09-2010, 06:17 PM
There are recovery machines with constant pressure regulator wich enables them to recover full liquid at entrance on recovery machine.
http://www.nice-year.com/yellowjacket/YELLOWJACKET%20%205-12.pdf