E-Series Air Flow Vacuum Controls

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Jan 6, 2021 | 07:14 PM

#16

maples01

Lead Driver

Joined: May 2004

Posts: 5,018

Likes: 132

From: Maryville

I put the check valve in the doghouse, so I have to pull it and fix it right, move it inside, I knew better but did it anyway, was a small one.

Jan 20, 2021 | 08:06 PM

#17

Fifty150

Logistics Pro

Joined: Oct 2007

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Thanks for sharing this write-up. Great job.

Aug 11, 2021 | 12:42 AM

#18

Westech06

New User

Joined: Aug 2021

Posts: 5

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I am glad I found this forum. My wife has been complaining about the AC going out as described above. Now that I know I will try this fix.

Sep 14, 2021 | 04:20 PM

#19

billybob12648

5th Wheeling

Joined: Apr 2011

Posts: 46

Likes: 3

GREAT INFORMATION, PHOTOS AND DIAGRAMS

Thank you JWA. This post was very well presented with all the info needed to accomplish the reservoir replacement. Your photos and diagrams made it easy to understand vacuum function and what needed to be done. Thanks again, billybob

Sep 14, 2021 | 04:25 PM

#20

JWA

Thread Starter

Fleet Owner

Joined: Aug 2010

Posts: 21,253

Likes: 1,656

From: Reynoldsburg, Ohio

Quote:

Originally Posted by Fifty150

Thanks for sharing this write-up. Great job.

Quote:

Originally Posted by Westech06

I am glad I found this forum. My wife has been complaining about the AC going out as described above. Now that I know I will try this fix.

Quote:

Originally Posted by billybob12648

I'm glad some are finding the OP helpful---having had my own struggles with this sort of thing once the solution was known I wanted to share it with others.

Dec 5, 2023 | 08:34 AM

#21

WarrensE350

Tuned

Joined: Aug 2013

Posts: 414

Likes: 1

Quote:

Originally Posted by JWA

I'm glad some are finding the OP helpful---having had my own struggles with this sort of thing once the solution was known I wanted to share it with others.

I'll echo the thoughts of others- excellent thread. It's taken me a lot of time to begin to understand the operation of my system. It is not a factory setup (installed by the conversion company based on everything I've learned), so I've had to figure out the rear HVAC on my own. For instance, no floor vents in the rear, only ceiling. So heat and A/C come out the same vents. I've figured out the heat, but still trying to get the rear AC working.

Thanks for this thread! (And many others on the subject as well).

Dec 5, 2023 | 09:03 AM

#22

JWA

Thread Starter

Fleet Owner

Joined: Aug 2010

Posts: 21,253

Likes: 1,656

From: Reynoldsburg, Ohio

Quote:

Originally Posted by WarrensE350

Is the front or factory-original A/C cooling properly?

Dec 5, 2023 | 09:12 AM

#23

WarrensE350

Tuned

Joined: Aug 2013

Posts: 414

Likes: 1

Quote:

Originally Posted by JWA

Is the front or factory-original A/C cooling properly?

Yes it is. Regardless of switch position (AC regular or recirc), there's only ambient rear air from the vents when the AC is on.

I can get heat to the rear vents if the selector is set to def or def/floor (took a while to figure that out; thought for years there was a problem with the rear heat as well, but learned that it is apparently designed this way).

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Dec 5, 2023 | 09:23 AM

#24

JWA

Thread Starter

Fleet Owner

Joined: Aug 2010

Posts: 21,253

Likes: 1,656

From: Reynoldsburg, Ohio

Quote:

Originally Posted by WarrensE350

If you have front A/C then most likely there is a refrigerant flow problem somewhere between the (front) compressor and evaporator. Any idea if your rear A/C system uses fixed orifice or an expansion valve back there?

Has your A/C system been recently checked or serviced?

Dec 5, 2023 | 09:29 AM

#25

WarrensE350

Tuned

Joined: Aug 2013

Posts: 414

Likes: 1

Quote:

Originally Posted by JWA

If this is an aftermarket conversion addition the no cooling aspect needs to be inspected and corrected if applicable.

That's why I have made such meager progress over the years. I don't even know if A/C was supposed to be available, since I can't find a single sentence about what system I may have or how it is designed to work. Heck, I don't even know who I could take it to who would know how to figure it all out. 27 years is a 'very long time ago' in the unknown aftermarket system installation world. Thanks again for the reply.

Dec 5, 2023 | 09:42 AM

#26

tabijan

Cargo Master

Joined: Sep 2012

Posts: 2,112

Likes: 286

From: Eastern TN

Are there refrigerant lines under the van? Do you have paneling off to see the rear air handler?

Sixto
07 E350 5.4 197K miles

Dec 5, 2023 | 09:51 AM

#27

WarrensE350

Tuned

Joined: Aug 2013

Posts: 414

Likes: 1

Quote:

Originally Posted by tabijan

Are there refrigerant lines under the van? Do you have paneling off to see the rear air handler?

Sixto
07 E350 5.4 197K miles

I haven't 'seen' any, but have looked under the van for them. If they're there, they may be hidden by 27 years of 'patina' perhaps?

I have had the panels off and have seen the rear handler. It's not anything like pictures I have seen here or elsewhere, though it is in the same place (behind the driver rear wheel). It's not open to access at the moment but wouldn't be hard to do if you have a specific question. There's a blue vacuum hose that is not connected to anything, nor does it seem to have any place to connect to. It runs inside along the driver's side up to the hidey-hole on top of the dash, where it also sits unconnected, with no apparent place to attach it. At this point, I think that's just a factory installed hose that would have been used if the factory system was installed, but?

Dec 5, 2023 | 01:11 PM

#28

tabijan

Cargo Master

Joined: Sep 2012

Posts: 2,112

Likes: 286

From: Eastern TN

Question 2: How does the control panel tell the rear air handler to blow hot or not hot air? In the factory setup, selecting the left half of the vent dial (model years with a rotary vent dial) channels vacuum, so to speak, to a flap that directs air through the evaporator to the ceiling vents. Selecting the right half cuts vacuum and air goes through the heater core to the floor vents. Your conversion system is different if it can send hot air to ceiling vents. If the blue line isn’t connected, how is a heater bypass effected?

When you switch from defrost to dash vents, does rear cabin air run cool immediately or does it takes a while? I’m thinking there isn’t a rear diverter but rather a valve that shuts coolant flow to the rear heater core, somehow running off the factory control panel. It would take time for the heater core to cool vs a diverter.

This follow-on should probably move off JWA’s original thread.

Sixto
07 E350 5.4 197K miles

Dec 5, 2023 | 01:19 PM

#29

WarrensE350

Tuned

Joined: Aug 2013

Posts: 414

Likes: 1

Quote:

Originally Posted by tabijan

I agree a different thread is a good idea. If a mod wants to make that happen, I'd appreciate it.

There are no floor vents other than the fronts. All air to the rear is through the ceiling vents. Rear heat begins when I switch to def/floor or def on the selector. The rear goes back to ambient temp air as soon as I move the selector to the left for any other position (slide switch style panel). A/C never blows out the rear vents in any position.