I have a 2008 Swift charisma 535 with the above heater fitted my problem is the heater when used on gas goes out after a few minutes and wont stay lit for any longer than a few minutes when re lit any solutions or suggestions before I take it back to my dealer.
Seeing how new your caravan is i would first ring your dealer, ask his advice and go from there. A good dealer should be most concerned and keen to help you.