Please can anybody help.I am at screaming point.Away in Autotrail 740s in Scotland.Heating and Water have been working fine.Then yesterday it packed up, no green light on control panel tried it on hook up no yellow light.Checked fuses by door,checked fuses in PSU all ok.Everything else is working fine.Luckily we have Diesel heating but no hot water.Look forward to hearing from somebody.Thanks.