FBH Webasto fuel burning heater ????

Im currently away on work ,and recieved a call from my wife in France ,worried about a smell and smoke coming from our 2005 tdv6.
The smoke and smell is coming from Unit located on the front righthand side infront of the battery,wife tells me it has a label stating Webasto.I think it must be a fuel burning heater from my research on line.
Yes its cold,but in the 2 years we have owned it we have never noticed a smell,i have seen the odd puff of smoke.Is this part serviceable!,does it know when it has to work(sensors)? Wife tells me when she switches car off ,she can here an electric fan sound coming from the FBH????.
Any help or advice would be greatly received

it will operate when the outside temp is below about 5 degrees c and untill the coolant is circa 77 deg c.

it sounds like it could do with a service but provided it is still igniting it should be fine for now. the smoke is just unburnt diesel and it will auto shut down if it doesnt ignite.

it probably just wants a good clean. you can get the gasket kits off ebay, webasto thermotop gasket set. carbon builds up in the combustion chamber.

i just strip mine down and fill the burner cartridge with caustic soda then pour in boiling water. it cleans it a treat, keep rinsing it a few times the dry thoroughly before re assembling. take out the glow pin when you are using the caustic tho!!

when its back on the car just give it a few attempts and it will start and run clean again!!

Regards

Gav