Sprinter-Forum    
 

Go Back   Sprinter-Forum > Sprinter-Based RV's & Conversions > Sprinter-Based RV Brands > Airstream > Sprinter Westfalia


 
Thread Tools Display Modes
Old 11-12-2018, 01:22 AM   #11
Robert Foster
 
Join Date: Nov 2009
Location: Charlottesville, Va.
Posts: 231
Thanks: 62
Thanked 34 Times in 26 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

Thank you very much for the replies.

All I had time to do today was check the voltage on the red and brown wires leading to my Digi-Max.

The brown negative did indeed have 0v on it when grounded to the brown common lug at the AC charger located in the wall below the kitchen drain board/storage area.

The red positive wire also had 0v instead of the much needed 12v.

So there's no voltage at the outgoing side of the fuse block terminal #4 and no voltage at the positive red wire leading to the Digi-Max. What is the assumed/typical relationship between these two wires ?

I was under the assumption that the relatively large capacity positive wire leaving fuse block #4 went directly to the Espar supplying all power needs of the Espar's fan, ignitor and ECU, with the red positive wire serving the Dig-Max coming from the Espar. Is this an incorrect assumption ?

When I removed my Espar to service it last year I do not remember seeing any type of inline fuse.
__________________
2005 Sprinter Westfalia
Charlottesville Va Home Inspector
Robert Foster is offline   Reply With Quote
Old 11-12-2018, 01:50 AM   #12
onemanvan
 
Join Date: Dec 2006
Location: Benson Arizona
Posts: 212
Thanks: 50
Thanked 136 Times in 84 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

Both the rheostat controller and Digi-Max get their power from an external source - IE: NOT from the Espar heater. Typically an installer would get power from the house battery. So trace the red wire connected to the controller back to it's source and determine where the fault is occurring - possibly an inline fuse. If that's not possible then add your own wire - IE: find a convenient nearby source for 12vdc - install an inline fuse near that source - run a new red wire from the fuse to the controller - 5 amp fuse should be adequate...

As you can see in the attached wiring diagram ( D2 & D4 have similar wiring ):

1) The controller gets it's power from the house battery via fuse 2.7.1 ( 5 amp )

2) The heater gets it's power from the house battery via fuse 2.7 ( 20 amp )
Attached Images
File Type: jpg espar wiring diagram.jpg (104.9 KB, 37 views)

Last edited by onemanvan; 11-12-2018 at 06:06 PM.
onemanvan is offline   Reply With Quote
Old 11-19-2018, 01:38 PM   #13
Robert Foster
 
Join Date: Nov 2009
Location: Charlottesville, Va.
Posts: 231
Thanks: 62
Thanked 34 Times in 26 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

Update.

The Espar is working as it should, actually better than it ever has, since this process motivated me to replace the rheostat with the Digi-Max.

My original problem of the Espar not coming on was indeed, as onemanvan pointed out, just a blown fuse in the positive line supplying the controller (formally the rheostat now the Digi-Max). That fuse, which I had totally forgotten about, is located in a weather resistant fuse holder that hangs out of the metal enclosure housing the Espar under the chassis.

I have run the Espar for multiple times for many hours since installing the Digi-Max and heat is now delivered more comfortably and consistently than it ever has been before in the four years since I purchased the van. I think the fact that the rheostat was located on the D pillar by the sliding door and subject to temperature swings and drafts while I installed the Digi-Max on the end of the upper kitchen cabinet partly accounts for the better heat delivery.

Thank you again for all the replies.
Robert
__________________
2005 Sprinter Westfalia
Charlottesville Va Home Inspector
Robert Foster is offline   Reply With Quote
The Following User Says Thank You to Robert Foster For This Useful Post:
Riptide (11-20-2018)
Old 11-20-2018, 01:06 AM   #14
Riptide
 
Riptide's Avatar
 
Join Date: Mar 2009
Location: CT
Posts: 273
Thanks: 57
Thanked 70 Times in 40 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

As I've said before, I might start putting systems on separate controllers where possible. Increasingly, I see the central computer in the overhead console as a single point vulnerability, and the fact that you can't get another one means you are dead in the water without it.

Nice work, Robert.
Riptide is offline   Reply With Quote
Old 11-20-2018, 01:08 AM   #15
Kiltym
 
Join Date: Jan 2015
Posts: 281
Thanks: 22
Thanked 31 Times in 26 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

You can get a replacement central computer. I posted a link here in another thread somewhere... Just FYI.
Kiltym is offline   Reply With Quote
Old 11-20-2018, 02:33 AM   #16
Robert Foster
 
Join Date: Nov 2009
Location: Charlottesville, Va.
Posts: 231
Thanks: 62
Thanked 34 Times in 26 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

Quote:
Originally Posted by Riptide View Post
As I've said before, I might start putting systems on separate controllers where possible. Increasingly, I see the central computer in the overhead console as a single point vulnerability, and the fact that you can't get another one means you are dead in the water without it.

Nice work, Robert.
I completely agree. The buttons for adjusting the refrigerator on my overhead console are less than perfectly responsive, which has me knowing they will fail me someday, but hopefully not before I remodel my interior.

Here's a picture of my Digi-Max installation. Easy to reach from the bed and keeping it off of an exterior wall were my goals, so the end of the upper cabinet was a perfect location and an easy place to route the cable to.
Attached Images
File Type: jpg DigiMax.jpg (52.1 KB, 29 views)
__________________
2005 Sprinter Westfalia
Charlottesville Va Home Inspector
Robert Foster is offline   Reply With Quote
Old 11-21-2018, 02:02 AM   #17
CaptnALinTiverton
 
Join Date: Dec 2011
Location: Tiverton, RI
Posts: 96
Thanks: 33
Thanked 15 Times in 15 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

Quote:
Originally Posted by Kiltym View Post
You can get a replacement central computer. I posted a link here in another thread somewhere... Just FYI.
Good posting all. Here is the link for the central electronics:
https://www.vwbusshop.de/epages/Guen...s/900001506048

I repaired mine twice by opening and cleaning/re-coating the contacts, some of which became almost impossible to use in cold weather. I would suggest cleaning first with alcohol. If no results, coat button pads with carbon contact paint. My first job only lasted a year so the second time I also re-coated the contacts on the circuit board but that was next to a nightmare. It required so much patience because it's so easy to short the interwoven contact fingers with the paint. It required magnifiers and toothpick application; lots of starting over with paint remover. I'd like to know a microelectronic company to do it the next time; but hopefully that won't be needed.


AL
CaptnALinTiverton is offline   Reply With Quote
Old 11-21-2018, 02:54 AM   #18
Robert Foster
 
Join Date: Nov 2009
Location: Charlottesville, Va.
Posts: 231
Thanks: 62
Thanked 34 Times in 26 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

CaptnAlinTiverton, are you able to give a readers digest version of how to remove and access the central computer and the contacts within, while avoiding any potential pitfalls ....?
__________________
2005 Sprinter Westfalia
Charlottesville Va Home Inspector
Robert Foster is offline   Reply With Quote
Old 11-21-2018, 02:59 PM   #19
OldWest
T1N Westfalia
 
Join Date: Jul 2009
Posts: 1,736
Thanks: 146
Thanked 480 Times in 366 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

Here's how OneManVan did it:

https://sprinter-source.com/forum/sh...ghlight=Remove

Other descriptions/instructions would be valuable too as different perspectives help.
OldWest is offline   Reply With Quote
The Following User Says Thank You to OldWest For This Useful Post:
Robert Foster (11-21-2018)
Old 11-21-2018, 06:29 PM   #20
CaptnALinTiverton
 
Join Date: Dec 2011
Location: Tiverton, RI
Posts: 96
Thanks: 33
Thanked 15 Times in 15 Posts
Default Re: Espar Heater/#4 Fuse Has No Power

Quote:
Originally Posted by OldWest View Post
Here's how OneManVan did it:

https://sprinter-source.com/forum/sh...ghlight=Remove

Other descriptions/instructions would be valuable too as different perspectives help.
He's got it right! The dome light comes out by just grabbing the clear plastic edges with fingers and thumb and moving forward or backward while prying down. You'll see the lips on the plastic when it releases. The tabs for the unit are more obscure but you can actually feel them on the sides of the unit when you stick your finger in the light hole and put pressure on each end while pushing forward (towards rear of vehicle). After unplugging connector, you want a clean work bench/table where you can sit for a while; with the unit face down, carefully pry the black frame away from the white box and lift the box away.

I used the carbon contact paint made by Caig but I found it to be flaky when dry. Just Google carbon contact repair; there's plenty there to study, especially what others have done. I did mention just cleaning with alcohol for first try but VERY LIGHTLY with Q-tip while being careful not to leave cotton hair. DON'T GET TOO WET OR RUB HARD; purpose of cleaning is NOT to remove contact material. (I didn't try stick-on pads fearing most stick-on's fall off and leave residue). The Chemtronics coating might be the best but it is twice the price. I always hate to pay a lot for chemicals due to their short shelf life.


AL
CaptnALinTiverton is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



All times are GMT. The time now is 10:56 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2018, vBulletin Solutions, Inc.