View Full Version : Running Auxilliary Heater on Espar Digi Controller

Boz Staggs
03-11-2013, 07:18 PM
I have a 2006 T1N with a factory Espar Auxiliary heater controlled by the factory timer. I'm interested in controlling the heater with an Espar Digi Controller instead of the factory timer. I want to be able to set the thermostat on the Digi Controller, rather than relying on the 120 minute max of the timer. Has anyone tried this? Do you have any thoughts?

Boz Staggs
03-15-2013, 05:09 AM
No one's tried this? That surprises me. I think I'll try it at the end of the summer and will report back.

03-15-2013, 07:30 AM
What do you mean by factory timer and how is the digital timer different? Quite a few owners have the comfort timer with seven day programming who could probably help answer any queries.

Generally speaking controllers are the simple rotary type / the comfort type or integrated into the CANbus and programmable with the 'wheel buttons.

Boz Staggs
03-15-2013, 09:11 AM
Thanks for the reply. This is what I have:


And this is what I want:


The difference is that what I have is an on off switch with a timer and what I want is a thermostat.

Does that help?

03-15-2013, 10:35 AM
Ahh, I see.

It's just a thought but you can get a slightly different version of your existing timer that has a thermostat, like this one. (http://www.melloronlineshop.co.uk/Vehicle_and_Marine_Heater_Accessories_plus_repair_ parts/100/Webasto_Air_Top_Combination_Timer_12v.html) Then it would just clip back into that slot in the centre dash.

Don't know if it's plug and play when used with Espar but I'm sure a dealer would know (or know how to wire it and make it so). I have this type of controller on mine with a Webasto, the thermostat is good to have.

Boz Staggs
03-15-2013, 11:12 AM
So, does yours have the 120 minute time limitation?

03-15-2013, 12:42 PM
There is the possibility that a factory fit heater may have a custom CPU programmed to talk to the van through CANBUS, but no-one seems to know whether or not Mercedes have taken up that option or use the heaters with the generic ECUs you would get for aftermarket install. I would suggest that if you have heater controls on the steering wheel, you have a specific CPU which may or may not work with other controllers. If you don't have buttons on the wheel, I would NOT take that to definitely mean you don't have a specific ECU. As to what custom options vehicle manufacturers use (enable or disable functions?) who knows? I understand that in the UK BT vans are a major source of D2s on ebay and have some different wires in the harness than are shown in any of the service manuals and can cause befuddlement for people trying to set them up in their conversions - mind you that is down the original end user rather than the vehicle manufacturer!

I think this is where ebay comes in handy - buy a second hand controller of the type you want (note that the new 701 series come in versions with 1 hour timer and without, and need an external thermostat which is extra, but can display fault codes, as I beleive can the type you have), if it doesn't work, put it back on ebay. It will cost you postage and listing fees but way cheaper than buying a new one to find it doesn't work!
Good luck!

03-15-2013, 01:05 PM
So, does yours have the 120 minute time limitation?

Yes. By "dealer" I meant "heater" rather than "vans"

Boz Staggs
09-07-2013, 03:19 PM
Great news! This week, Jim Rixen accomplished my goal of making the auxiliary Espar heater run off a thermostat instead of the timer. He just pulled out the timer and wired in a thermostat which now sits just above my cup holder. The timer is still in place and functioning, but I can also use the thermostat. My next step is to relocate the thermostat to the rear of the van and to replace the analog model with a digital battery-powered model. This is a great and inexpensive mod which will make winter camping much more comfortable. :laughing:

12-17-2018, 02:32 PM
Hi Boz,
Were you able to relocate the thermostat to the rear and have it function properly for winter

12-17-2018, 03:27 PM
I have had success using this (https://www.amazon.com/Inkbird-Temperature-Controller-Fahrenheit-Thermostat/dp/B019I3YCFS) thermostat to fire off the factory Espar..