My starter battery is being drained by .4amps and it is the fridge that is doing the draining. Why does the fridge run off the starter battery ? Is this normal? why not the leisure battery? I have had to get a start from the ferry company the last 3 times .The fridge works perfect, is it a bad earth? I am confused, please help somebody. My van is a Lunar roadstar 780 built 2005.