Aux Heater Override Switch

[kish]

Hi Folks,

 

Has anyone fitted a DIY override switch for the aux heater? Or bought a low cost kit, possibly with a timer.

I'd be very interested to hear from anyone who has done this. The wiring diagram on the Mirez web page 

http://www.mirez.co....Information.pdf

 

shows that you would only need a double pole switch to give 12v to the temp sensor and engine on sensor inputs. Would this be all that's needed? Would the electric water circulation pump also come on automatically?

 

Any thoughts?

 

Cheers 

 

[marinabrid]

i fitted one to our mk1.   i simply ran a wire from each of the temp sensor pins   located under the wiper scuttle,  ran them to a used heated rear window switch i got off ebay,     so now  i decide when to use the heater,  mine never seemed to come on when it was cold   even though i put a new sensor on,    so as long as the water temp isn't up to normal     i can switch on the heater and switch off when i like. 

[kish]

Aaah, brilliant. What about with the engine off? Does the auxillary water pump come on as well?

 

Thanks

[SilverBeast]

It won't work with the engine off as I believe it also gets a signal that the engine is running. The auxiliary pump will run all the time the ignition is on and for a few minutes after switching off on models other than the 130 and 150 tdi's

[marinabrid]

if you are trying to override it  so you can have a warm car before driving off   i think thats a whole new subject,  I'm sure some clever bods on here have done it  though i think its a costly and complex matter with new wiring and relays time switch clock and a small battery that has to be fitted under the seat. 

why didn't someone who designed these motors  simply arrange it like that in the first place,   it would be great to simply programme it to come on 1/2 hour before you want to drive off in a warm car.

[chrispb123456]

It's quite complex to do the aftermarket fit to run the heater independently from the engine, ideally you should have a second battery with a split charge relay to avoid running the main battery flat or do as I did replace the original battery with the biggest that will fit in the carrier.

Ebersp

[steve329]

My old works van had a pre heater with a programmable timer it was so nice in the winter walking into a war nice free van at 8am! If my gal was diesel I would deffo be looking at putting a Time clock mod on the pre heater!

[chrispb123456]

Just An idea the airtronic type heater could be an easier option, this is the type the trucks have to keep us poor lorry drivers warm at night, this type just warms the air in the cab and has no connection with the vehicle's heater.

[kish]

Thanks for input. I think the largest possible battery is the easiest (but not the best) solution for using the aux heater with engine off.

 

So basically I need to override the outside air temp sensor, the 'engine on' sensor which are both on the eberspacher. Then I either need to have the ignition on to run the aux water pump or have that pump switched on independently. Could be don't with one switch maybe. Just need a wiring diagram! Some of the wires are under the wipers, I understand.

[chromedome]

I hope you have a working aux heater to start with..........................

[kish]

Yes, that's another issue. I think a new glow plug should fix that though.

[MadBaz]

Turning the gal into fully independent heating and integrating it into the existing electronics is quite complex. I've done it without a second battery but it required 5 relays, a time clock, a delay off relay, a 2ch pulse timer (for the alarm & blower), 3 switches and around 30 metres of cable. I can completely control the heating now, next project is to add rf/gsm control at a reasonable price. Edited April 24, 2014 by MadBaz

[teett]

As the preheater upgrade kit contains components about in 20...70EUR value, I didn't want to pay 300+ EUR for Eber or Webasto upgrade kit. So I bought 2 relays, 3 fuse holders, cables and connectors for less than 20EUR. And I'm planning to build a timer controller with bluetooth connection and Android app. But you can also buy a simple 12V 7days timer and a delay timer relay for coolant pump from eBay with 10...20EUR (coolant pump should run a minute after stopping the aux heater).

So if you have skills in electric work or electronics, you can upgrade your aux heater with less than 40EUR :)

 

I also made a little overview manual of my upgrading process: http://ims.ut.ee/~teet/preheater/preheather-manual.pdf

 

And also shorcuts to Eber and Webasto manuals:

http://ims.ut.ee/~teet/preheater/eber-manual-de-en.pdf

http://ims.ut.ee/~teet/preheater/webasto%20manual.pdf