DIY - Red Tek conversion

[ohlone]

Howesight, Wow! Many thanks for this crafted forum response.

A question for you / others:

Your instructions state to put a can of Red-Tek into the high-side service port. I'm a complete A/C noob but from what I've scoured online I thought it was a universal and dangerous no-no to add refrigerant to the high side of any A/C system ?

Gracias.

[Abscate]

When the system is evacuated it’s safe to add to the high side port. But it’s safer and slower to use the low side,especially for us occasional ACtechs.

Our Volvo fleet doesn’t even come with high side ports, but you can monitor pressure in software
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[Butcher]

You can fill on either side, but the compressor needs to be off if you want to fill on the high side.

It's just sound principle to never fill on the high side.

[blurat]

It has been mentioned a few times so if anyone misses it........

Install first can to a vaccuumed system on the high side....WITH THE ENGINE OFF, NOT RUNNING, NO SOUND COMMING FROM THE MUFFLER, NO KEY IN IGNITION IT IS IN YOUR POCKET SO YOU KNOW WHERE IT IS.

Otherwise you cant pick your nose anymore.

[Jon Folks]

Hi guys, having trouble with my redtek conversion. Just rehabbed by AC: new compressor, drier, expansion valve, trinary switch, parallel flow condenser. I flushed the lines and evaporator.

With everything hooked back up I ran a vacuum pump for 1.5 hours and the system held vacuum for 48 hours.

When I went to add refrigerant, the system only took about ~1.5 cans before I get pressure readings of 30 low 120 high. Doesn't seem right, what could I be doing wrong? Since I am already at 30PSI I stopped adding refrigerant for now.

Thanks!

[JudoJeff]

Jon,
Add more. By weight it will take 18 ounces, each can is 6, assuming you got all of it in. Go by vent temps, not pressure readings.
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1989 Vanagon GL Westfalia Camper, Burned up on 7/31/16.
1987 Vanagon GL Westfalia Camper, Bostig & Rebuilt, sold
1986 Vanagon GL Westfalia Camper, Bostig Sold May 10, 2021
1999 Ford GTRV Westfalia camper (30% bigger Westy layout)

[Westaru]

I was ready to install today but I've read the whole thread but still have an unanswered question - the Redtek kit comes with a low-side fitting only. How are you all filling through the high side?
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1984 'Westaru' Vanagon Westfalia EJ22
@UtahWestfalia on IG

[bobbyblack]

Stock low and hi are the same. Fittings added for R134A are size diff, perhaps you can get an idea on that. I didn't care much for the upsidedown hi side trick, went from the low side. BUT, could have. Don't forget the box fan... I used 2..
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'87 Westy 'Flossie','86 Westy 'R1','86 tintop GL - Subi2.2 'J2','83.5 stock tintop L 'ZoomBus','74 Karmann Ghia, '63 Notch

[Westaru]

[Westaru]

[mbwesty]

What, no, not the high side! I hope ur just joking, and if I don't hear back from you I would assume you may be in the hospital!

[bobbyblack]

I'd say that the up-side-down thing sounds scary no matter what, but I do believe it CAN be employed with success. Anyway, I got my adapters off an EJ22, and neither of them fit the stock stems hi or low. I scrounged up a Freon filler, and adapted back to the newer stuff from that. Nuts, yes, but worked just fine from low side, it DID take a LONG time tho. Patience payed off tho, super cold. I'm happy! TWO box fans, seriously. More if you can figure out how!
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'87 Westy 'Flossie','86 Westy 'R1','86 tintop GL - Subi2.2 'J2','83.5 stock tintop L 'ZoomBus','74 Karmann Ghia, '63 Notch

[mbwesty]

I think I also used more than 1.5 can, may be it was like 3. The pressure reading was hard to conclude I remember as it fluctuated a bit. May be watch to make sure that it doesn't get above 35's the way to go. Also, I had a cheap HF guage, I don't think it was made for the Redtek stuff, so it's gonna be off.

Anyother thing, I refill it basically once a year with one can, the low side would go from 20 back up to 30psi and I call it good. The van gets cooler...I hope this help!

[Westaru]

Thank you all for the comments.

Mbwesty, Howesight recommends installation of the first can with engine off in his writeup on pg 50 (I can't figure out how to direct link to that thread).

So is the trick simply using all 3 cans through the low side, non-inverted and it taking a long time? Heating cans with hot water?
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1984 'Westaru' Vanagon Westfalia EJ22
@UtahWestfalia on IG

[mbwesty]

Ah, si, the system is still in a vacuum environment. I think the only time I ever used the high side was for the first filling, and it was just to be sure of the high side pressure was legit. I think with the system in a vacuum, the Redtek would just escape into the system. The first can I put in had oil I believe, I also filled the compressor with oil first. I am also very sure that I filled it with the can inverted and didn't use hot water...

[dhaavers]

[fxr]

[Westaru]

Thank you all for the tips! I attempted the Redtek install yesterday and hit some speed bumps.

First, the background: I installed the Smallcar AC kit and originally had the R134A installed. However the air could have been colder and wouldn't keep the kids in the back seat cool (especially when 100* here) and the pressures were high enough that the high speed fan would run almost continuously even when on the highway (at 100*).

I decided to give the Redtek a try to lower pressures, reduce fan operation and hopefully reduce temperatures further.

The first 2 cans went in to the low side fine, 1st quickly and the 2nd took slightly longer. Both were held upright and put in bowls of hot water to help them discharge. Took roughly 1hr for both, first when the car was not running (discharged into 28# vacuum) and running on the second. Discharge temps after the second was around 64*, box fan running, low and high speed fan cycling periodically, and garage temps of 99*. Lowside pressures were 22-25 and high side was 225-250 (depending on operation of high speed fan).

Third can is where I screwed up. I started the filling, went to check temps, and noticed it had climbed to 74* at the vent. I went back and turned off the valve but for whatever reason this can discharged much quicker and was nearly empty. Almost 3 cans total, 31-33 psi low side, 225-275 psi high side. I tried to bleed off some refrigerant slowly but couldn't do it slow enough without releasing oil. I then noticed that the high side gauge had filled with refrigerant in the sight glass. Waited an hour, and was still full of refrigerant when I disconnected it.

To summarize, basically I have no idea how much refrigerant I have in the system other than 'too much', releasing it doesn't seem to be working without losing oil, and it works much less well than the R134A did.

I'm evaluating my options now and debating on releasing slowly and measuring the oil released (catchcan), and then trying this again with Redtek/Envirosafe or just going back to the R134A and be done with it.

Is there that much performance gain to be had with Redtek/Envirosafe vs R134A? My system has barrier hoses and is designed for either, so it's really a performance question at this point.

Secondly, have any of you had the high side hose fill your sight glass/hoses with refrigerant? Assuming I did something wrong but would like to learn exactly what!

Lastly, is Envirosafe comparable performance wise to Redtek? The shipping times with Redtek took a while last time (2 weeks).

Thanks for any advice you can give.
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1984 'Westaru' Vanagon Westfalia EJ22
@UtahWestfalia on IG

[djkeev]

High pressure high side is a result of the gas being unable to drop the heat at the condensor.

You need some serious cooling air flow through the radiator.

Dave
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http://www.thesamba.com/vw/forum/viewtopic.php?t=392473

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[dhaavers]

FWIW, I had similarly poor vent temps until I tried charging with the engine
cover laid in place (to keep engine heat out of the cabin) & hatch closed as
much as possible (to recirculate cooled air inside cabin). YMMV...

- Dave
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86 White Wolfsburg Westy Weekender
"The WonderVan"
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