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Memphalia Sat Jul 24, 2010 2:34 pm

Okay, so I bought my 1989 Westfalia about 2 months ago. YES I HAVE REPLACED MY FUEL LINES AND TIRES!!!! HA HA! I just fixed a leak and had my a/c charged with R12 the air blows cold from the rear vents when I use the controls to the right of the radio, but I do not get any cold air from the front vents. How do I get cold air from the front vents? What are the functions if the two ventilation controls to the left of the stereo?

Williamtaylor33 Sat Jul 24, 2010 2:39 pm

The vents up front are fresh air vents.
The Cold air is only from the rear.

Memphalia Sat Jul 24, 2010 2:45 pm

That is what I was afraid of. Thanks for the quick reply!

singler3360 Sat Jul 24, 2010 4:51 pm

We bought a 12V oscillating fan at a truck stop. With it clipped to the poptop lift bar and facing forward, it circulates the cold air farely well (enough to stop the dog from panting in the front seat).

campism Sun Jul 25, 2010 11:10 am

Memphalia, be sure to close those dash vents, since you don't want hot air coming in the front while your A/C is trying hard to blow cold from the back. Also, somewhere there is a post by someone who removed the grey A/C enclosure from over the back seat (it bolts up to the ceiling under the bed and you need to remove the mattress pad to get to several long screws) and inside it he added foam blocks in strategic places to channel the cold air. The result of this is that the air from the blower is then being blown through "tunnels" inside the enclosure instead of through a large open plenum, for better routing of the moving cold air.

I have not done this foam block mod yet. I did remove the grey plastic A/C enclosure entirely for a different reason and left it off so far and find now that the air from the A/C fan blows straight forward, making the front seat passengers comfortable even on the hottest days.

Sir Sam Sun Jul 25, 2010 11:22 am

To add to that the foam filter pad on the AC evaporator is likely so clogged with crap that your AC unit is fighting to pull air through it.

Memphalia Sun Jul 25, 2010 11:54 am

How do i get to,
clean, and/or replace the filter that may be restricting air flow?

Sir Sam Sun Jul 25, 2010 2:54 pm

Memphalia wrote: How do i get to,
clean, and/or replace the filter that may be restricting air flow?

Its the filter on the backside visible when the rear door is open, you can at least vacuum it easily.

Terry Kay Sun Jul 25, 2010 11:57 pm

The evaporator foam is covering the whole thing--it's all wrapped up in old crumbling black foam.
Drop the evaporator box, clean off all of the old foam.
\
Now for the key move--
Blow out the evaporator with compressed air.
Get ALl of the injested garbage outa the coils.

You'll find all kinds of new found AC air volume.

Typhon2222 Mon Jul 26, 2010 7:03 am

campism wrote: I did remove the grey plastic A/C enclosure entirely for a different reason and left it off so far and find now that the air from the A/C fan blows straight forward, making the front seat passengers comfortable even on the hottest days.

Huh. You're saying that removing the forward-swooping grey plastic enclosure increases air flow to the front?! <scratches head>

It would sure open up a little headroom too. And I'm guessing you get another foot or two of usable length up in the "spice rack"?

Anybody else done this? I'd love to see some photos of how the car looks without this thing.

VisPacem Mon Jul 26, 2010 7:27 am

Is it advisable to just remove the old crumbling foam and NOT replace it ?

campism Mon Jul 26, 2010 8:24 am

"Huh. You're saying that removing the forward-swooping grey plastic enclosure increases air flow to the front?! <scratches head> "

Sorry if I was unclear. What I'm saying is this: The A/C in my van used to blow hot and I never had it blowing cold while that enclosure was in place, but I removed the entire Westy interior for rust check and soundproofing and never reinstalled that enclosure. Got the A/C blowing cold and still have not reinstalled the enclosure but when I do I will do the foam block channeling inside it before I do to help ensure that the airflow is as good as it can be with the enclosure in place.

As it is now, the cold air blasts straight forward from the A/C cabinet from a rectangular hole about 3" x 12," without restriction. The only downside is a slightly unfinished look to that cabinet surface due to the exposed routered slot that the rear edge of the now-missing enclosure fits into.

Incidentally, having that enclosure gone does increase headroom over the rear seat. I'll take a picture so you can see how it looks.

campism Mon Jul 26, 2010 9:05 am

Here you go:


You can see that it looks a little unfinished but is not objectionable. I could probably use grey modeling clay to fill the slot, or most likely will modify the plastic enclosure as previously described and reinstall it.

Using the net for storage while driving the A/C on is not recommended, as anything in the net will probably block the flow of air. Storage only while parked or while driving in non-A/C weather.

Typhon2222 Mon Jul 26, 2010 9:42 am

Campism, thanks for the detailed description, and pic! Nice.

Hmm, I'm really tempted now to remove the enclosure.... My wife, who is 6'2", would appreciate the extra headroom. And I'd love the extra foot or so of space in the spice rack.

As you say, some grey putty would fill in the slot nicely too.

To help the cold air reach the front without the enclosure, Singler3360's suggestion sounds great: dangle a 12v clip-on oscillating fan from the poptop lift bar, pointing forward. I think our local Kragen sells them for $13 or so.

Those metal eyelets which are anchoring the bungee cords in your pic are those screwed into the holes originally used to hold up the A/C enclosure? Neat.

I'm curious about those metal stud-like things projecting forward from the A/C cabinet, the ones underneath and flanking the air exit hole. What do they do? Can they be removed?

campism Mon Jul 26, 2010 10:47 am

"I'm curious about those metal stud-like things projecting forward from the A/C cabinet, the ones underneath and flanking the air exit hole. What do they do? Can they be removed?"

I think they might be clips for a filter or something. The two previous owners had lots of A/C work done to the van (apparently without success) so I don't know what OEM stuff might be missing. I found a metal louvered grille at HoDepot that covers them and that hole exactly but have never installed it, figuring it might also interfere with the air flow to the front. I think the additional fan might be unnecessary, so if you are planning to remove your enclosure you might want to do that and test first to see if the fan is even necessary. We get LOTS of air up front.

EvilDNA Wed Jul 28, 2010 12:52 pm

I just finished my A/C rehab with RedTek and "The Search". For a few days, I had not re-installed that plenum. I just put it back on and the air flow was drastically reduced.

I've contemplated taking it back off and doing a non permanent aesthetic mod to get back that massive airflow back. Prior to that, I'm gonna try the 12v clip on fan trick and see if that solves things.

No doubt, without that plenum thingy bolted up, it's hurricane gales. Comes out with such glorious volume that I noticed my speed dropped by 5 mph. J/K.

As for the AC rehab, I can only say three things. 1. RedTek 2. Use the Search 3. Listen to Terry Kay. Nuff Said.


Moderator edit: So y'all don't have to go searching for it, the master RedTek topic: https://www.thesamba.com/vw/forum/viewtopic.php?t=292488 .

Typhon2222 Wed Jul 28, 2010 1:11 pm

EvilDNA wrote: I just finished my A/C rehab with RedTek and "The Search". For a few days, I had not re-installed that plenum. I just put it back on and the air flow was drastically reduced.

I've contemplated taking it back off and doing a non permanent aesthetic mod to get back that massive airflow back. Prior to that, I'm gonna try the 12v clip on fan trick and see if that solves things.

No doubt, without that plenum thingy bolted up, it's hurricane gales. Comes out with such glorious volume that I noticed my speed dropped by 5 mph. J/K.
:D

Man, now I'm really tempted to take off the plenum/enclosure. Hurricane gales sounds awesome.

If the plenum reduces airflow, could somebody please tell me why VW (or Westfalia) introduced them at all when they switched to the gray interiors? What was the point? <scratches head>

campism Wed Jul 28, 2010 1:48 pm

Looks nice. Style over substance.

EvilDNA Wed Jul 28, 2010 1:54 pm

I wonder that same thing. The older rear AC cabinets just have the vent at the blower, no plenum ducting. I've had the van for years (3rd vehicle) and never tackled the A/C until now. (no longer a third . . called up to the majors now)

As a side note, I bought a wireless thermometer from La Crosse that can have 3 additional sensors added in order to measure my air temps. The only way you can truly monitor your A/C's effectiveness is to know what the temps are coming into the evaporator and coming out.

I have Sensor 1 mounted at the evaporator's air intake (rear of van). Sensor 2 is mounted directly at the blower vent (middle of the two openings). Sensor 3 is just in front of the plenum vents.

What is interesting is that I'll see a 20 degree drop in my temp from Sensor 1 to Sensor 2. (I still think I can get more . . . must talk w/ TK). But at Sensor 3, it's back up 10 degrees. So, after running around for a bit, I was seeing 65 . . down to 45 . . . up to 55 degrees at vent.

Terry K mentions he can get 36-38 at vents, but I should clarify that this isn't a hop into the van and run to McD's, etc. It takes time to push down the ambient temps in the van.

What I need to verify from Terry K, is what kind of rear system he has. Pre or Post Plenum. Because that Plenum run kills blower temps by a full 10 degrees in my system. If he gets 36-38 degrees right at the blower vent, then I am getting close. If those are post plenum temps, I'm waaay off.

I'll still collecting data and need to double check my Hi/Low pressures to ensure nothing is leaking . . . etc. (vacuum did hold prior to loading system). But right now, the plenum is bumming me out on air flow and exit temps.

For now, the 12v fans are a cheaper/easier solve than a plenum re-pull and re-face job. The whole A/C rehab had me nervous but in the end, it's been less daunting than I had originally imagined. I will say that I got lucky thus far. No major system failure. Only had to clean out lines, replace the basics, i.e. dryer, expansion valve, o-rings, and charge system. Well, the cooling fan resistor did fail but a trip to my boneyard set me straight. Lucky, indeed.

campism Wed Jul 28, 2010 2:44 pm

EvilDNA,
You are being a lot more scientific about this than I have been. What I have learned has been by poking around and remembering some of what happened. Also, I've been extremely lucky (and I know it) with my cheapo R134A conversion from AutoZone that I only need to recharge once or twice a season.

I plan to go through the system and clean it out, already have the expansion valve and receiver/dryer and need to buy the O-rings, so once things are less miserable in my gravel driveway I'll get that project underway. Meanwhile, your plenum discovery and with/without comparison makes me less likely to reinstall mine for any reason.



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