# Eberspacher D5WZ Heating System



## teemyob (Nov 22, 2005)

Hello 

Anyone have a MB Sprinter with the heat booster button option?

We have a MB Sprinter MH and it has the Mercedes Factory fit Eberspacher D5WZ hydronic heater to boost engine heating.

There is a kit available to convert the D5WZ to a fully programable auxilary heater.

Have any MB owners who have this unit done this?

Trev


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## trek (May 1, 2005)

*MB 2008 Sprinter:- Booster to Auxilary Heater upgraded*

Just upgraded my 2008 NCV3 Sprinter that came with a Booster Heater (only works with engine running ) to the Auxilary Heater (which also works as an engine pre heater - demister cab warmer etc & can even be preprogrammed to come on at a set time)

My MB dealer has removed the Heater Booster Code HZ9 and added the Auxilary Booster Code H12 in the EZS Control Unit using the STAR computer whilst linked online to Germany and now I have a fully working Auxilary water heater

All credit to my dealer who perservered to complete this work, they had to send a request to Germany to change the codes (FDOK Authority required ?) then when they logged back on with the STAR computer and connected my NCV3's ECU to the Computer in Germany the upgrade was downloaded to my Sprinter

I can now even set 3 different start times via the onboard computer, so I can set the heater to come on say 30 mins before I plan to start the sprinter.
As I don't have the steering wheel controls this has to be done using the M,0,-,+ buttons on the display,

Additionally we had to replace the Booster switch (639 545 33 07) with the dual position Auxilary switch (639 545 19 07) and run a single wire from the new switch to the heater

check out the diagram on page 21 of this document:-

http://www.espar.com/tech_manuals/Ap...1__DE_8460.pdf

look for the B2 connector with the 4 wires going to the switch which shows 3 leds , (red , yellow & the white one to illuminate the switch when side lights on)

& 2 switches , the STH switch is the stationary heater & the ZH switch the booster heater

run a new single wire from the new switch pin 2 to connector (4 way ) on side of espar heater pos 2

ON my heater this 4 way connector (labelled as S2 / B2 on an ESPAR document that I have) has :-

a purple & black wire in position 4 that goes to the switch pin 7 
(this is the ON/OFF control for the heater - same wire for both aux & booster - the booster switch has a 500 ohm ? resistor in circuit to ground where as the aux switch is a full ground)

a purple & green wire in position 1 that goes to the switch pin 9 (this is an LED indicator )

my new wire in position 2 that goes to the switch pin 2 (this is an LED indicator )


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## twinky (Aug 11, 2008)

Well....................you did ask    .


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## teemyob (Nov 22, 2005)

*Eberspacher*

Hello Trek,

That was in 2006, managed to get a kit and wired it all in to the main panel.

Will reply to your PM regarding the New Frankia Sprinter.

Thanks,
Trev.


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