Rear heater - confusion,,

[bernard1973]

My 1988 Caravelle 1.6d has got a heater underneath the rear seats which I'd always assumed just worked from the hot circulating water the same as the front heater. However in the manual it says the heater is switched on/off with a green knob which lights up (and I've got) and that it's supplied with fuel from the vehicle tank??

Can anyone help clear this up?

[Oldiebut goodie]

Knob is for optional extra - either an Eberspächer air heater or Webasto water heater - possibly has been removed if you can't find it. Photo of under seat looks like the standard rear heater working from the engine coolant to me. Lever on the side needs to be moved to open the valve to allow the coolant to flow.
Tidy it up! Midget gems go sticky.

E D I T:
The Webasto BBW46 water heater is covered in the Bentley manual section 82.18.

[bernard1973]

Knob is for optional extra - either an Eberspächer air heater or Webasto water heater - possibly has been removed if you can't find it. Photo of under seat looks like the standard rear heater working from the engine coolant to me. Lever on the side needs to be moved to open the valve to allow the coolant to flow.
Tidy it up! Midget gems go sticky.

E D I T:
The Webasto BBW46 water heater is covered in the Bentley manual section 82.18.

Cheers mate, I can't find any other heater apart from the one under the seat. It works perfectly which is lucky as we slept in the van last night

[footstuck]

hi mate
On a German Army Radio van (DOKA type) i had, the night heater was underneath and positioned forward of centre between the central chassis rails. It was all boxed in and unidentifiable as a heater till you removed the tin work. when you twist that green knob Clockwise (i think) it should illuminate and start the ignition sequence