TheSamba.com :: View topic - Front in dash AC evaporator as a rear system "Booster"

Fri Apr 01, 2016 6:32 am

Dave,

Your stamp says 04/86, mine says 10/86. I think yours is a '86 model, and mine is an '87. Do you agree? Very slight differences overall, I'd guess.

Also, do you have the Flash Silver LP7Y/X9 paint like mine? Looks very similar at least. Im still waiting on a response in the paint thread for anyone who has a good rattle can (temporary solution to cleaning up a variety of PO's poor touchups) ?? I'd really like to find a Rustolium brush on or roller color match as well, saw a thread from across the pond, but I can't find US solution to same, and also missing the color match number in that paint.

Also, I can't remember if you sourced your new "under-dash" to be installed "in-dash" unit new, or if there is alternate source. I totally LOVE the idea of front A/C !!! Are you thinking of cutting the case to put an outlet into the Vanagon front heat box, so some of the air goes through the stock vents?

Fri Apr 01, 2016 7:19 am

djkeev wrote: I Have several balls in the air right now, sliding door, trans reseal, axle repack.

The road salt is almost gone and hoping for a ride soon. :lol:

Dave

I (selfishly) hope the slat stays so we get more progress from you. Thanks for forging ahead.

Fri Apr 01, 2016 7:57 am

vanis13 wrote: djkeev wrote: I Have several balls in the air right now, sliding door, trans reseal, axle repack.

The road salt is almost gone and hoping for a ride soon. :lol:

Dave

I (selfishly) hope the slat stays so we get more progress from you. Thanks for forging ahead.

My thoughts exactly! 😀😜

Fri Apr 01, 2016 11:33 am

Hi Dave:

I cannot recall whether you used an aftermarket parallel-flow condenser or not. If not, then you will likely find that the stock VW unit will be barely adequate for a dual-zone system. There are two reasons - - parallel flow in part and the "gap" in part. The "gap" hinders the rad fan's ability to draw air through the condenser.

As for your compressor, I strongly suspect you will not need to add a second compressor nor need to increase the size. Initial cool-down of your hot van after sitting in the sun may take your compressor to the limit, but that is really just a few minutes of running.

With my rig, (single zone, front evaporator only) I found that sealing the condenser to the rad with thick foam weather stripping was very important to performance. On the highway, ram air does the job, but for stop and go traffic, a perfect seal is the only way to ensure the rad fan draws the air through the condenser.

Here is a link to a 2009 collection of text and photos and schematic by a fellow who installed dual-zone AC in his Vanagon and used dual condensers:

http://autos.groups.yahoo.com/group/subaruvanagon/...Condenser/

You will need to join the Yahoo Subaru Vanagon group to access this. The author, Ed MacLean, used his Vanagon in the hot Southwest states.

Fri Apr 01, 2016 2:01 pm

Howesight, thanks for the link, I'll need to join I guess.

I did put in a new r134a cross flow Condensor! :lol:
My old copper one was road salted into dust!

In a frenzy of optimism this afternoon, I ordered the AC refrigerant hose and fittings that I will need to plumb this new Evaporator into my existing system.

I had used the EZ-Clip system so making changes is quite easy!

Interesting, the size 06 Tee and the size 10 Tee are off the shelf units!
Maybe what I am doing is not so far fetched? :?:

While I haven't pulled my dash....... YET!
I have begun puzzling out how to plumb the AC into the heater box.

I had reworked my heater box to recirculate cabin air by drawing it into the intake section BEFORE the blower fan.

Here is the link to it. 10cent has a flap available now for $225 so that would be an easier solution to the ram air shut off than what I made.
http://www.thesamba.com/vw/forum/viewtopic.php?t=651327

You would still need to add my intake pipe as I did or something similar. (When 10cent comes up with an in dash AC mod to add to his ram air shut off flap kit....... I want a cut! :wink: ) (Small car uses the Vintage Air unit with modifications (poorly executed) 10cent and his eye for quality could take my Nostalgic Air UD-110 concept and work miracles with it!!!! )

http://www.thesamba.com/vw/forum/viewtopic.php?t=605822&highlight=

*************
(From the above link)
Using my Multimaster and a File I shaped the pipe to fit the Heater Box.

It took many test fits and a little off here and a little off there but I ended up with a good fit......

I traced the pipe with a Sharpie onto the Heater Box.......

And using my MultiMaster cut away the Heater Box.......

Cleaned up the edges with a file, cleaned the pipe well and glued the pipe to the Heater Box, held it in place with a length of tape.......

Inside the Box viewing the Cabin Air Pipe........

Now to let it cure, then make sure it is well sealed. Maybe some silicone used intelligently?

***************

Because of this heater box modifucation I will not only blow cold refrigerated air into the Heater Box with the built in fan on the UD-1100 but also suck it in with the stock heater fan.

My intake system is made out of 2" ABS plumbing pipe. I used ABS because I could effectively glue it to the Vanagon's ABS heater box.

I have a 2" pipe protruding from the heater box.

So..... In a wave of excitement, off to the plumbing I went store and brought home a length of 3" ABS pipe..... Why 3"?...... Because this unit is also made of ABS and when I removed the rectangular vent face frame, I have a 3" x 16" opening.

By slicing the 3" ABS lengthwise, just off center I end up with a round exit duct.

I will then reduce this 3" exit duct to 2" and connect it to my heater box.

I'm 3/4 done with it already! I tested the airflow even, its GREAT!!!!!

Getting the vent face off wasn't hard. After examination and utilizing some common sense I Determined that it was simply clipped on.
Two small screw drivers and Viola' it's off!

My 2" ABS pipe from my heater box mod.....

My new 3" ABS pipe.......

My test slice, I went as much over 1/2 as I could and then filed the cut edges to nicely squeeze the Evaporator box......

Test piece on the Evaporator.....

I liked the result so I sliced a longer piece in the same manner.....

I used my angle grinder with a 40 grit flap wheel to flatten the cut to seal against the Evaporator.......

Next I removed the fan switch and the temp switch from the Nostalgic front bezel and tucked them inside for now. (I turned the fan switch to high beforehand) and then I duct taped one end shut and the pipe to the Evaporator.....

I taped some paper towel to the exit vent to show how well it moves air.....

I do thinnk that the air will exit somewhere mid span rather than at the end because of the piping on the heater box and useable space.
I took a short length on 2" ABS and chamfered it to fit the radius of the 3" pipe.
I am guessing this is how and about where the air will exit into the heater box.....

Dave

Fri Apr 01, 2016 2:36 pm

Why do I feel that I'll be removing my dash on Sunday? (Saturday is my Grandsons 5th Birthday Party! He's an April Fool's day baby!

My Delrin roller for my sliding door is lost in the mail anyway...... :roll:

Dave

Fri Apr 01, 2016 2:48 pm

Did I miss the part about how the condensed water on the evap unit will escape? I am just wondering how it will drip all over my project if YOU don't show me how it works right on yours ;-)

Fri Apr 01, 2016 2:51 pm

bobbyblack wrote: Did I miss the part about how the condensed water on the evap unit will escape? I am just wondering how it will drip all over my project if YOU don't show me how it works right on yours ;-)

The Nostalgic Air UD110 unit has two drain holes molded into it. I'll attach drain hoses (included) and drain them out...... Somewhere......

You can see one of the drain ports in this photo (by the blower fan wires)

Dave

Fri Apr 01, 2016 8:27 pm

Dave,

Hold on to your hat.

Why are you wanting to divert a direct blast of vented cold air away from the cabin and in through ducting, into the heater box, in around and through all of this hardware, when the most efficient way to get the air into the cabin would be right out of the vents of the evaporator all by itself?

I know what your trying to do, but I am real sure you're going to lose some volume here.

Fri Apr 01, 2016 8:30 pm

Go, Dave GO! Love this thread!

8) 8) 8)

- Dave

Sat Apr 02, 2016 4:30 am

Terry Kay wrote: Dave,

Hold on to your hat.

Why are you wanting to divert a direct blast of vented cold air away from the cabin and in through ducting, into the heater box, in around and through all of this hardware, when the most efficient way to get the air into the cabin would be right out of the vents of the evaporator all by itself?

I know what your trying to do, but I am real sure you're going to lose some volume here.

I've been with Air Cooled VW's as a daily driver back before they were hobbies and were my source of transportation 24/7/365.

I fought the old air ducts, the lackluster delivery of warm in January, and yes, I've used an ice scraper on the inside of the windshield!

I added fans, I patched rusted holes, I've done it all. My experience was before Air Boxes for the most part, 1955 - 1968.

That's my entire Auto air flow resume.

But......

Decades in Home Construction and Remodeling taught me a LOT about air flow. Proper duct sizing, main trunks, damper valves, hot vs cold, fan size, noise, etc etc etc.
I fully understand the effects of restriction on air flow, those handy flexible snake hoses are the worst! Sucking up volume like an air flow magnet!

I am entering this concept with my eyes wide open.
I am working with subpar raw ingredients. There is only so much air that can be moved into the Heater box. That air then passes through another fan, pushed through the heater coils, and out various orfices only to travel down long rough pipes to a vent!

This is why I was so excited a few posts ago that the new Evaporator will not only PUSH Cold Air out of the Evaporator but the Heater bix will be sucking it in at the same time.
Yes, there is only just so much air that can be moved through a 3.14" area of pipe. Add length to that 3.14" and get volume, now you've got some movement restriction too!

I am not destroying the Evaporator, only doing non invasive modifications,

If reak Works use shows me that tge Evaporator works but air delivery is anemic I can always rework a few installation details, flip it around and install it so the vents blow out above the glove box. Not ideal but would address your concerns.

Hey, my Grandfather, an electrical engineer, worked for Thomas Edison back in the early 1900's, you tried things...... if it failed...... Well ...... you tried something else! (England has talking Movies Introduced to King George V by my Grandfather)

Thanks for the thoughts!

Evaporator is here, Refrigerant hoses are ordered........

Smile, The opportunities to shout "I TOLD YOU SO!!!!" Are expanding! :wink:

Dave

Sat Apr 02, 2016 5:15 am

The unit looks like it fits so well above the glovebox, why complicate things at this point?

Mark

Sat Apr 02, 2016 5:23 am

crazyvwvanman wrote: The unit looks like it fits so well above the glovebox, why complicate things at this point?

Mark

Do you have one installed already?

Believe me, while it does fit well, the complication is minimal.

It is a matter of installing the unit with the fans towards the oassenger blowing towards the front into the already modified heater box or cutting my dash to accept the AC vents needed with it positioned with the fans towards the front blowing towards the rear.

Honestly, putting it into the heater box will be easier and less invasive.

Dave

Sat Apr 02, 2016 7:52 am

Your are the taskmaster--still. :wink:

I was just thinking , rather than busting your stones trying to divert the air directly outa the expansion box, going round & round and back down to the heater box after slowing a direct air flow into the cabin , why go to all of the work?

Go for it, see what happens.

Me?
I'd jump right on the tornadic blast right outa the box, and skip reinventing the wheel.

I wouldn't ever lay an "I told you so" on you.

I'd more than likely just pop an --"Hey Dave you f'ed up a little" on you. :lol:

Problem here is, you'll never know how much cfm you cut yourself out of by the diversionary, re-routing tactics.
Looks like the air will be slowed down by making that left turn direct out of the vents direct into that PVC tubing air dam.

Just thinking.

Sat Apr 02, 2016 9:39 am

this is a neat project. however I had ac in my van (no longer works as hoses have leaked and I really do not care for ac, hence I never fixed it) and my old ac when it did work blasted lots of cold air to the front. the big duct above the windscreen would pump out lots of cold air, freeze me out even in 100 F outside temps.

maybe your stock ac has a problem other than a design flaw that is causing lack of cooling up front?

Sat Apr 02, 2016 12:19 pm

bluebus86 wrote: this is a neat project. however I had ac in my van (no longer works as hoses have leaked and I really do not care for ac, hence I never fixed it) and my old ac when it did work blasted lots of cold air to the front. the big duct above the windscreen would pump out lots of cold air, freeze me out even in 100 F outside temps.

maybe your stock ac has a problem other than a design flaw that is causing lack of cooling up front?

Camper vs hardtop.....
My AC us 100% rebuilt and works great..... We like cold air blowing on us directly.

No big duct to the front.

Dave

Sat Apr 02, 2016 12:32 pm

More thinking;

If you took a couple of half mooned directional baffle plates so when the air is hitting them as soon as it leaves the evaporator , it would immediately send the air down that tube the right way, instead of hitting a dead end.

This may work better.

Sat Apr 02, 2016 12:45 pm

djkeev wrote: bluebus86 wrote: this is a neat project. however I had ac in my van (no longer works as hoses have leaked and I really do not care for ac, hence I never fixed it) and my old ac when it did work blasted lots of cold air to the front. the big duct above the windscreen would pump out lots of cold air, freeze me out even in 100 F outside temps.

maybe your stock ac has a problem other than a design flaw that is causing lack of cooling up front?

Camper vs hardtop.....
My AC us 100% rebuilt and works great..... We like cold air blowing on us directly.

No big duct to the front.

Dave

oh, so,it is a camper. how is the stock camper ac set up? do you have some photos to post of how the orignial camping ac is set up? I dont recall seeing an ac in a camper, so I have no idea how it was set up originally.

ps Mine is the eary style ac with no duct running length of van back to front. mine has the cold coil on the ceiling just behind the front seats, with a small duct to bring cold air to the front ducts that is mounted just above the sun visors

Sat Apr 02, 2016 4:02 pm

David is trying to bring an evaporator set up up front similar to what you got only not going to be giving him brain freeze as your suffering from.

How can you post such erroneous stuff when you don't even possess common vanagon knowledge?

Yea, the camper stuff is all in front of the back window, I can't, I don't believe , have a real hard time figuring, you have missed this, you don't know, and allegidly being of the automotive expert status you seem to often falsify..

It turns out , you really don't know too much.

Sat Apr 02, 2016 4:05 pm

bluebus86 wrote: oh, so,it is a camper. how is the stock camper ac set up? do you have some photos to post of how the orignial camping ac is set up? I dont recall seeing an ac in a camper, so I have no idea how it was set up originally.

^

Early campers:

Late campers:

A lot of us late camper owners have removed ^that duct/plenum to get more air flowing up front.
http://oldbluesblog.com/files/RemovingthePlenum.pdf
**Do NOT rehash the plenum vs. no-plenum argument in this thread!! Go to the plenum topic for that!**