I have an Eberspacher Airtronic D4 Plus 12v (4kW) Heater.
I think it may not be kicking out as much heat as it did previously. I have only owned my boat for about 9 months. To my knowledge the unit has never been serviced.
Is there anything I can do to improve its performance?
I am sure I can remove it and send it in for an official service
(at great cost). However I would rather avoid that as it still seems to be operating pretty well.
The unit is from 2008.
Any advice on user servicing would be great.