DPD Air Conditioning for type 2 bus? FAQ

[69BahamaYellow]

Totally agree with Skills on the logic behind buying an off the shelf Gilmore or ICE system. No matter what they charge for it, you will spend less money going that route than building a custom system, given all the time you will save.

For me, I just like the challenge of projects like this.

[69BahamaYellow]

So I finally found at least some of the parts I need to configure a working DPD air conditioning system for the whole bus.

This picture shows the evaporator unit fully disassembled for cleaning. I had to remove about 3 lbs of dirt dobber nests from the fans and evaporator coils, but it cleaned up pretty good. I tested the fans and they work great. These things move a very high volume of air! After seeing the size of the actual evaporator coil in this thing, I feel pretty confident it actually will cool the whole bus quite well.

Next step is to locate the front half of the evaporator unit housing (the white piece of plastic that contains air vents and control knobs for the front seat passengers. Unfortunately that piece did not come with this unit, so if anybody has one of these for sale, please PM me.

I'm going to have my standard 55amp alternator rebuilt at a local shop to a 90 amp output to handle the extra load from the evaporator and condenser fans. I'm also going to purchase a parallel flow condenser and Fan's from Omega.

I'm still undecided on a compressor, since I'm still considering an under dash evaporator for the front and a rear evaporator under the back seat as a dual evaporator setup, if I can't find all the parts I need for the DPD overhead unit. With the dual evaporator setup, a variable displacement compressor is the way to go, but if I go with the single evaporator overhead DPD unit, a fixed displacement rotary compressor will be best.

[mango-smoothie]

has anyone tried the universal kits on ebay? they are from USA

example:
http://www.ebay.com/itm/A-C-KIT-UNIVERSAL-UNDER-DA...mp;vxp=mtr

obviously this one would need customization to fit a bus, but it's a new clutch type compressor and a reasonable price.

this particular one is a little small to cool a bus, but i'd imagine you could increase the evaporator size and add another fan.

[69BahamaYellow]

I did a little cleaning on the evaporator coil I found, while I'm waiting on replies for more parts.

The TXV was the first thing I removed. It was completely clogged and has a superheat set for R12. I'm going to use 134a refrigerant, so I found a replacement TXV that has the same size inlet/outlet O-Ring fittings (with the correct superheat for 134a at my local autoparts store. Turns out it's a match for a rear A/C unit for a 1984 Chevy Suburban. I got this for $15 brand new

I've also got a home made flush kit I use to flush and pressure test the coil. simply pour in A/C flush fluid with a funnel and rubber hose, then blow it through the coil with compressed air and collect in the mason jar (I added a fuel filter to trap all the crap that comes out, which allows you to re-use the fluid for several forward/reverse flush cycles. I'm glad I did this, because the flush fluid that started crystal clear was almost black after several flush cycles.

After a flush and pressure test with 150PSI air; no leaks confirmed.

Final step was to install the new TXV and wrap with insulation tape, just like the original. I should also mention that there are 2 O-ring seals here that also need to be replaced with the green ones that are suitable for 134a. The black ones that came on it originally were hardened and cracked when I removed them, and would have certainly leaked refrigerant.

I'll caution anybody else trying to refurb one of these old DPD units, that every hose and seal has to be replaced or it will leak from day one. This is no small task, and since no off the shelf parts exist any more, you have to custom make every hose and fitting, then leak test every one (because the hydraulic shops that can crimp on new fittings to custom length hoses, don't always do it right). Like others have said, buying a complete, ready built system from ICE or Gilmore would be way easier, but there are those like myself, who just enjoy the process of bringing one of these things back to life.

[mango-smoothie]

did you put 150PSI into that glass jar?

[mlesniak]

http://www.thesamba.com/vw/classifieds/detail.php?id=1814423

im selling the one I took outta my 1973 transporter. its more slick than the other ones pictured previously. very nice fit, however I have no use for it
_________________
Rosita the 73' Tin-top

[69BahamaYellow]

Ha. good catch on the glass jar. It's vented, so it will only catch and filter the flushing fluid, without building any pressure. To do the pressure test, I plugged the hose that was going into the jar.

Mlesniak, I'm interested in your DPD unit. I sent you a PM. Still can't find a front section for the one I have, and yours appears to be complete. Probably has the same internals, so I can transfer parts if needed to make a complete one.

[SGKent]

the insulation tape you used looks like electrical tape. It was common to use a black rubberized cork back in that day so it would not sweat and collect mold.

example:

_________________________________________
_________________
“Most people don’t know what they’re doing, and a lot of them are really good at it.” - George Carlin

[Tcash]

DPD Air Conditioning

http://www.thesamba.com/vw/archives/manuals/heat_ac_shop_manual.php
http://www.thesamba.com/vw/archives/manuals/dpd_ac.php
http://www.thesamba.com/vw/archives/manuals/1976_bus_dpd_under_dash_ac.php
http://www.thesamba.com/vw/archives/manuals/1979_bus_dpd_under_dash_ac.php

http://nostalgicac.com/compressors.html
http://www.vintageair.com/
http://www.gilmore-enterprises.net/
http://iceautoair.com/index-2.html
http://www.eaton.com/Eaton/ProductsServices/Hydraulics/Fittings/PCT_259178
https://coldhose.com/
http://www.ebay.com/itm/NEW-ADJUSTABLE-YORK-TO-SAN...mp;vxp=mtr
http://www.ebay.com/itm/NEW-YORK-TO-SANDEN-AC-COMP...mp;vxp=mtr

[secretsubmariner]

DUDE. Please keep posting about this. I'd love to bring back my DPD. I've decided I'm already going to re-install it and use it as a fan for now.
_________________
-Tony
ᏣᎳᎩᎯ ᎠᏰᎵ
1978 Champagne Edition Bus FI
1970 Auto Fastback FI

[69BahamaYellow]

Good callout on the cork insulation tape by SGKent. That's the same stuff I wrapped around mine, it's the stuff sitting on top of the roll of electrical tape in my pic. However, the adhesive backing on my cork tape was not holding tight on it's own, and would unravel overnight, so I wrapped some electrical tape on top of it to keep everything in place.

[SGKent]

[Goshen]

I bought this unit yesterday and i am going to attempt to make it all work.. I am not sure what to do here but i am hoping someone will chime in..

In the event that i am not able to then i will be selling it.

I plan on using it in my '67 Split

_________________
My '64 Pan Meyers Manx Dune Buggy "Lady in Red"
https://www.thesamba.com/vw/forum/viewtopic.php?t=659260

My '67 Split Window Bus project :
http://www.thesamba.com/vw/forum/viewtopic.php?t=634144

My '67 Maserati Blue Oceano Bug Build:
https://www.thesamba.com/vw/forum/viewtopic.php?t=541870

[Goshen]

I spent most of the day working this DPD unit but it will not fit my Split plus I don't have the budget to undertake the task to get it all working.

So I will post if for sale for $150.00

_________________
My '64 Pan Meyers Manx Dune Buggy "Lady in Red"
https://www.thesamba.com/vw/forum/viewtopic.php?t=659260

My '67 Split Window Bus project :
http://www.thesamba.com/vw/forum/viewtopic.php?t=634144

My '67 Maserati Blue Oceano Bug Build:
https://www.thesamba.com/vw/forum/viewtopic.php?t=541870

[MikeSoCal]

Here is a post on Ebay for some original parts: http://m.ebay.com/itm/191714119137?_mwBanner=1
_________________
Restoring a 1971 VW Westfalia

[69BahamaYellow]

I've been acquiring parts for this dpd rehab project, so it's been a while since my last post. I located the front section of the overhead unit from another Samba member, and I also acquired a nice fixed displacement Denso compressor with single V-belt pulley that fits nicely to the side of the fan housing, without butchering the engine tin. Finally, I located a high output alternator to cover the extra power demands from the evaporator and condenser fans. Will post some pics soon.

[69BahamaYellow]

Here are a couple of pictures of the overhead unit installed for mockup. I still have the guts of this unit out to keep the weight down, since that makes it much easier to drill the holes in the roof. Right away, I discovered a problem with the design of the overhead unit vs the under dash system. I'm 6' 2" so my head can hit the overhead unit if my bus is ever rear ended. In normal driving, it's awesome, because it's not in your line of sight and the vents are pointing right in your face. I think I can bend the posts on my seat headrests to bring them forward enough to prevent the concussion risk in a rear collision, but I may also need to make some kind of foam pad to attach to the overhead unit for some additional protection. If you're under 6' tall, there's little risk of hitting your head on these things.

The fit of this unit is actually pretty good, but the 38 year old parts needed some stress fractures repaired with a little fiberglass....

More to come......[/img]

[69BahamaYellow]

Here's a picture of the front section installed:

I also found a nice compressor from a 1998 Mazda MPV that seems to fit the available space pretty well. Will need to make up some brackets next...

[busdaddy]

[69BahamaYellow]

I checked with the manufacturer (denso) about the compressor rotation, and this one works the same with either clockwise or counterclockwise rotation, you just have to keep the suction/discharge port orientation up, or it will not get properly lubricated. This compressor is a fixed displacement (170cc) swash plate 10 piston design that is used in tons of cars (so a rebuilt one only costs between $125-$155. There are also lots of port configuration possibilities by just changing the manifold (4 bolt plate) on the top of the compressor. I walked around my local junkyard, and found this exact compressor on at least 20 different cars. Some had manifold plates that exit straight out the top, some were side exit left (like the one I got), or side exit right. I like my configuration because it will require no cutting of the engine tin for the hose connections. I made some mounts with 3/16" angle iron.

Perfect pulley alignment, but very little clearance between pulley and oil cooler and heater blower duct

Finally, here are the mounting dimensions for the base. Angle iron was used to lift the compressor off the blower fan housing about 1 inch for proper clearance. Now I've got to come up with a separate belt tensioner, since the mounting flanges on this compressor are not set up to pivot the compressor for belt tensioning. Hopefully someone else will use this info to inspire their own AC install and give me some ideas on a tensioner design

Here's what the OEM crankshaft pulley looks like (it's a v-belt type), but I bet you could have a 4 to 6 rib serpentine pulley made up, using the original engine fan spacer as a guide for the hub. That would give the option to use a compressor with a serpentine pulley (which gives a little more clearance for the compressor)