DIY: Replacing factory Espar heater with new off-the-shelf

vanski

If it’s winter, I’m probably skiing..
so the ncv3 guys who have engine off furnace need to fool the ecm into thinking the ambient temp is lower. and they don't power up the ecm in order to get it to work. i'm fairly certain putting a 22k ohm resistor on a spdt switch on the amb temp sensor wire will work.
 

Midwestdrifter

Engineer In Residence
I am pretty sure its not the espar that is preventing the high temp start. It is likely the ATC unit. The ATC is probably getting the ambient temp from the cluster I would guess. The cluster comes out of sleep very time you open a door, or press a button on its face. It reads the external temp directly. If you are using a manual control scheme, you should be bypassing the ATCs logic completely anyways?
 

vanski

If it’s winter, I’m probably skiing..
Perhaps.. but then why do all the earlier factory installed Espar models, the several I’ve worked with and several others folks have worked with, fire up at any temp? It could be 105f outside and they will fire up. :idunno:
 

kentonius

enough to be dangerous...
To all interested in replacing their factory Espar with an off-the-shelf new unit:

It works! The only modifications needed to gain the factory functionality of
1) Booster Heater and
2) Aux Heater w/7-day Timer
- Connect sprinter side of smaller secondary harness to a +12V signal. I used the yellow wire on my Espar (sprinter-side) harness.
- Connect both blue and yellow wires together on Espar (sprinter-side) harness. These are signal wires only (very low amps) but are needed to activate the heater.

I'm sorry it took so long to come to the conclusion that it really is not very hard to replace the factory Espar with an off-the-shelf new unit. I tested it today at +52 degrees F and the aux heater (7-day timer bacon button) fired it right up. Shut down procedures also verified.

Thanks to Vanski for the background details and the encouragement! Thanks to everyone else on here for the background help to this and so many other projects I've attempted on the Sprinter due to your helpful threads elsewhere here.
 

kentonius

enough to be dangerous...
Are you connecting BOTH wires of the small harness (Sprinter-side) to 12V signal?
Whoah there! No. I only connected the purple wire, not the brown one. The brown one I just removed from everything as it was an extra ground wire. It didn't even connect on the Sprinter side. My sprinter side small harness just had a small blue wire with yellow stripe (i think) that plugged into the small espar harness that had both purple and brown (brown didn't have anything to connect to). So I just cut the harness from the old espar, and connected the purple wire to the yellow wire on the sprinter larger harness.
 

VinceP

2005 158" High Roof Pass.
OK. But you strip and join together the blue and yellow wires on the sprinter-side harness? I'm puzzled because you mentioned you need both bacon buttons "on" for your Espar to work which is not the case for me. So I am wondering If I need to do that... I guess it'S gonna be a "try and see"....

That sounds fairly easy to do. I'll order the heater from Heatso.
 

kentonius

enough to be dangerous...
OK. But you strip and join together the blue and yellow wires on the sprinter-side harness? I'm puzzled because you mentioned you need both bacon buttons "on" for your Espar to work which is not the case for me. So I am wondering If I need to do that... I guess it'S gonna be a "try and see"....

That sounds fairly easy to do. I'll order the heater from Heatso.
My guess, as well, is try and see - but to confirm that the Espar ordered from Heatso worked perfectly!

Please let us know your experience as well!
 

chrismac

Member
Ok, so I recently ordered this same heater from Heatso, installed, and ran it fine. It works. I do not have the 7-day timer but do have the DPTP switch modification combined with the REST function to operate the heater without the engine running, works as intended as well. 2006 cargo. Thanks to Kentonius for checking this out. You can tell the van is just so much happier when hot!
 

outbound

06/2500/140
so... am about to get underway on this same project
(as soon as a piece of exhaust hose arrives, had to mangle the heater-end to get the old one out).

my '06 doesnt have the 7day timer, only REST and booster functions - so will likely start with vic's method
but am hoping someone can offer a 'consensus' on what's the best way to go about re-configuring
the existing van controls to run the D5 as an engine preheater,
as well as run the REST function as a backup for the D2, as Mwd mentioned above..
ultimately all running on the house bank vs the crank batt, using one of the timers
(at some point anyway, dunno about getting to all this out in the cold)

here's what i've learned, far as sourcing the exact replacement D5 unit...

the '06 OEM install is MB's 'proprietary' model (according to espar NA/ontario, who told me ONLY MB can help with):
D5WZ / mod# 25 2343 / MB pt# 005 830 80 61 (this # is THE key bit of info)
was able to source it locally, via spec order from germany, at both the freightliner ($580) and MB dealer($650)
'10days to 2wks out'
(and ONLY because i finally found the MB pt#, since they 'dont speak espar' at the dealers, so had no idea what to replace it with..)

BUT... i ended up buying it from ecstuning.com (forget now who it was here that pointed us to them),
who shows a listing for the 25 2344 /MB# 0058308161, which has the 2nd 2wire connector-cord, for 519bux

however... after figuring out how their dbase/ numbering system works (with the MB pt# the key to it all),
tried changing the pt# on the URL from:
https://www.ecstuning.com/b-genuine-mercedes-benz-parts/ventilation/0058308161/

to the 25 2343 model and VOILA! up she came:
https://www.ecstuning.com/b-genuine-mercedes-benz-parts/ventilation/0058308061/
priced - at that moment - at 380bux
(they showing it now at 544.75, so mustave been a data entry screwup, mightve been their cost vs retail price?)
so i immediately clik'd and ordered the buggah! (and they honored the price that eye first saw it at = SCORE, hopefully it all works out)
it arrived as scheduled, '2 to 3 wks out', from germany (made in poland)
is exact unit as the OEM (only 1 cable/connector).

so... so far, so good - just waiting on the piece of exhaust hose to get here and...
ABOVE FREEZING TEMPS, to go out and install it.
(i got very acclimatized to the wx in my prev location, so it takes me awhile to get used-to the cold, after just getting used-to the heat here in summer!)
that and we're stuck in 'the inversion zone' so there's bluesky&sunshine up there somewhere, just not down here in the valley!
(so mights well just go play up in the canyon today and hope it clears off up above... ;)
:rad:
 
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vanski

If it’s winter, I’m probably skiing..
so... am about to get underway on this same project
(as soon as a piece of exhaust hose arrives, had to mangle the heater-end to get the old one out).

my '06 doesnt have the 7day timer, only REST and booster functions - so will likely start with vic's method
but am hoping someone can offer a 'consensus' on what's the best way to go about re-configuring
the existing van controls to run the D5 as an engine preheater,
as well as run the REST function as a backup for the D2, as Mwd mentioned above..
ultimately all running on the house bank vs the crank batt, using one of the timers
(at some point anyway, dunno about getting to all this out in the cold)

here's what i've learned, far as sourcing the exact replacement D5 unit...

the '06 OEM install is MB's 'proprietary' model (according to espar NA/ontario, who told me ONLY MB can help with):
D5WZ / mod# 25 2343 / MB pt# 005 830 80 61 (this # is THE key bit of info)
was able to source it locally, via spec order from germany, at both the freightliner ($580) and MB dealer($650)
'10days to 2wks out'
(and ONLY because i finally found the MB pt#, since they 'dont speak espar' at the dealers, so had no idea what to replace it with..)

BUT... i ended up buying it from ecstuning.com (forget now who it was here that pointed us to them),
who shows a listing for the 25 2344 /MB# 0058308161, which has the 2nd 2wire connector-cord, for 519bux

however... after figuring out how their dbase/ numbering system works (with the MB pt# the key to it all),
tried changing the pt# on the URL from:
https://www.ecstuning.com/b-genuine-mercedes-benz-parts/ventilation/0058308161/

to the 25 2343 model and VOILA! up she came:
https://www.ecstuning.com/b-genuine-mercedes-benz-parts/ventilation/0058308061/
priced - at that moment - at 380bux
(they showing it now at 544.75, so mustave been a data entry screwup, mightve been their cost vs retail price?)
so i immediately clik'd and ordered the buggah! (and they honored the price that eye first saw it at = SCORE, hopefully it all works out)
it arrived as scheduled, '2 to 3 wks out', from germany (made in poland)
is exact unit as the OEM (only 1 cable/connector).

so... so far, so good - just waiting on the piece of exhaust hose to get here and...
ABOVE FREEZING TEMPS, to go out and install it.
(i got very acclimatized to the wx in my prev location, so it takes me awhile to get used-to the cold, after just getting used-to the heat here in summer!)
that and we're stuck in 'the inversion zone' so there's bluesky&sunshine up there somewhere, just not down here in the valley!
(so mights well just go play up in the canyon today and hope it clears off up above... ;)
:rad:
If you have a D2 routed from your house bank, don't do the full blown, correct (as in all circuits are routed through relays to keep the OEM/start batt circuits separate from the house batt circuits) way, just do the method outlined by VIC with the SPDT switch and use it as a motor pre heater on those particularly frigid Utah days. If you plan on having the D5WZ as your primary heating source, then you will need to do the mod the correct way which takes at least 5x the time and appropriately size your battery bank as an average of 6amp/hr is a lot current to draw over a long period of time... I liked (past tense as I've sold that rig) my D5 only, it kept my well insulated 140 plenty warm, setup but I also had a 500 amp hour battery bank and 300 watts of solar up top which kept everything happy.

:2cents:
 

outbound

06/2500/140
thanks for piping up here vanski! (your posts tend to be GOLD in these matters)

eye hear you on the D5 as backup for the D2, but i'm running with a 400ah housebank + 200w PV..
(along with a bluesea boat type 1-2-both selector switch to jump the house to the eng-alt, no probs noted thus far)

summer ops (with 12vdc refrig AND the D2 for chilly high-country nights) typically use 50-60ah/nite
winter ops - D2 running appx 16hours - along with refrig + cooking (mostly electrically when ccccold)
will burn 80-90ah/nite - or appx 20-25% of bank = plenty to spare should i need the D5 as backup.

am thinking that the best bet to reconfig the vans ckts is to find the various fuses that power
the HVAC blower, the D5, its pump etc and 'cut the buss' to remove those ckts from the vans system.
have already run some 10/2 ancor from the house breaker panel to under the driver seat to do this,
along with running the van radio, so to completely remove all house-function drains from the crank batt.

and i'm pretty sure this wont be without complications - just gotta figger out what those might be.

with a bit of luck (never mind skill) and between you, kentonius, vic, --dick, et al's inputs, methinks we can pull it off!

:bow:

shall we give it a go?
 
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Midwestdrifter

Engineer In Residence
I think it may be simpler to just find the power feeds for the low speed fan, pump, and D5. Then install a SPDT relay on each, and run them all back to a common Aux feed. That would be a bit cleaner, and everything reverts back to stock starter power when the relays are de-energized.
 

outbound

06/2500/140
I think it may be simpler to just find the power feeds for the low speed fan, pump, and D5. Then install a SPDT relay on each, and run them all back to a common Aux feed. That would be a bit cleaner, and everything reverts back to stock starter power when the relays are de-energized.

(didnt mean to leave you out of my list of experts Mwd! your .02 is also gold here :)

you might be right, but that would seem more involved than just 'cutting the buss' to isolate those
functions from the van's system?
 

Midwestdrifter

Engineer In Residence
I am not sure if all those use the same feeds/bus. If you are okay with those items all running from your aux bat 24/7, then that is a good approach as well. The ATC is canbus connected, but shouldn't care where it gets it 12V power from. All the sensors attached to the ATC get their ground a 5V supply internal to the ATC as well.
 

outbound

06/2500/140
I am not sure if all those use the same feeds/bus. If you are okay with those items all running from your aux bat 24/7, then that is a good approach as well. The ATC is canbus connected, but shouldn't care where it gets it 12V power from. All the sensors attached to the ATC get their ground a 5V supply internal to the ATC as well.
nears i can tell... (uh oh.. he's speculating again...)
no issues running all that stuff from the housebank - since when underway (after an overnight)
i've got the house connected to the eng-alt anyway.

the question would seem to be: will the canbus be messed up by seeing +12 'backfed' via the ATC
from a different source? (this is where my automotive elec tech comes to a screetching halt ;)
 

vanski

If it’s winter, I’m probably skiing..
while you're at it, it's nice to route the primary ATC fan wire through a relay so you have all 5 speeds (0-4).. so nice when you come back from skiing and you can just crank that thing and warm up the hands... just don't leave it on #4 (5, @0-5) when unintended as you'll drain your house pretty quickly.
 

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