Anyone ever use a freon recovery machine? - PeachParts Mercedes-Benz Forum

andrewjtx · #1 01-07-2011, 02:33 PM

I'm trying to finish the dismantling of Betty. Pretty much the last things left are the engine and the A/C system.

I found a used Robinair 17400 (R12 only) recovery machine that was being liquidated by a local school district maintenance shop. Came with two empty cylinders.

Order some new gauges followed instructions to hook everything up. Blue line going to the port up on top, red line down behind the alternator. Yellow line goes into the machine. Hooked up the cylinder in same fashion with yellow line going to air purge port.

The only thing I wasn't able to do was to run the A/C system before beginning the recovery. Engine & electrical system is completely offline at this point.

Opened the valves on the gauges and cylinder, gauges should about 40psi on both side. Started up the machine in the order the manual states and everything sounds right. Compressor is on & so forth. Let it run for a while and the gauges don't go down. I'm expecting this to start pulling stuff out of the system, no?

Now, as a test, I shut it all down. Closed all the valves and checked to see if anything was in the cylinder. Cracked the gas valve open just a little. It had gas in there now, which it didn't before. But to shake the cylinder, I hear no condensed liquid in there. Should I?

Hooked it all back up and left it running for hours. Same thing.

Robinair says that the compressor will shutoff when done. How long should I expect a recovery of 3lbs R-12 to take?

TX76513 · #2 01-07-2011, 02:38 PM

Look and see if there are any dates on the filters. Also if in its previous life it inhaled some Freon Stop Leak there could be some problems. My Robinair takes 2 filters but not sure about the R12 setup. Is yours digital with an air-purge option?

andrewjtx · #3 01-07-2011, 02:46 PM

nono.

This is an older one. Robinair doesn't even list it on their site any more.

All of the functions are very manual. Knobs on the back for air purge, oil drain, and accumulator pressure.

It has one inline filter that has changed part numbers and it has the original part number on it now. So I think it's old.

Luckily, a new filter is only $55 and I can get it next day from D/FW.

I'll see how well it works after a new filter.

Graplr · #4 01-07-2011, 02:52 PM

I bought a used one from a shop as well. Got a pretty good deal. The manager didn't know what he was selling. For $100 I got a charging machine with a 30 lbs cylinder with about 5 pounds in it, a recovery machine with about 30 lbs in the recovery tank.

The recovery worked well for about the first three times I used it. I think it took in to much oil and stopped working so well. I think the filter plugged but I haven't needed to use it since so it is still sitting in my garage as is.

When it was working it only took a minute or two to empty the car's system. After what I assume was a plugged filter, I noticed results similar to yours.

TX76513 · #5 01-07-2011, 02:52 PM

Is the filter infront of the wheels and goes across the entire front?

lietuviai · #6 01-07-2011, 03:02 PM

I've always wondered if just having a large empty freon tank with a good vacuum pulled on it would accomplish the same thing?

andrewjtx · #7 01-07-2011, 03:09 PM

Quote:

Originally Posted by TX76513

Is the filter infront of the wheels and goes across the entire front?

Yes, it's this one:

Just placed the order w/ Amazon. $55. Hoping this is all it needs.

@Graplr: Nice deal. Mine was $200 for the machine and two cylinders. Does yours have the oil drain knob on it?

andrewjtx · #8 01-07-2011, 03:10 PM

Here's the actual machine. Robinair 17400

vstech · #9 01-07-2011, 03:23 PM

mine is similar to that one.... full size cabinet with vacuum pump, and cryogenic pump for recycling...

andrewjtx · #10 01-07-2011, 04:56 PM

I don't think this one has a vacuum pump, just the compressor. In the manual it shows a standalone pump being placed in-line between the manifold outlet and machine inlet. But it doesn't say a vacuum pump is necessary for recovery. Only for evacuating the machine and/or the car.

rscurtis · #11 01-07-2011, 05:31 PM

If your filter has Schrader valves in each end, be sure the hoses connected to it can depress them.

andrewjtx · #12 01-07-2011, 05:46 PM

Haven't taken the filter out yet, so I can't say. But the lines are copper and the fittings are very tight.

lutzTD · #13 01-07-2011, 05:54 PM

Quote:

Originally Posted by andrewjtx

I don't think this one has a vacuum pump, just the compressor. In the manual it shows a standalone pump being placed in-line between the manifold outlet and machine inlet. But it doesn't say a vacuum pump is necessary for recovery. Only for evacuating the machine and/or the car.

from what I understand the compressor in the unit will evacuate the system, no need for the vacuum pump until you finish the service, you will need to vacuum evacuate all of the air let in while the system was open. For recharge you will need a scale or column, the modern machines have all of this incorporated in one machine. I have the same robinair machine as the original poster but I have not tried to use it yet.

Quirky Mercy · #14 01-08-2011, 02:51 AM

Is your unit working now after the filter change? You should see some movement of the needles on your manifold gauge set when in operation. It should only take about 5-10 minutes to remove the refrigerant from your system with warm temps.

andrewjtx · #15 01-08-2011, 10:15 AM

Just ordered filter yesterday. Probably arrive next week.