Bourton 2011 water heater controls...new owne

Hi, I am a bit mystified by the manual instructions in my new to me van!

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There is this, near floor by wardrobe........and another which says truma ultra heat on left panel by rear door......can anyone help me to sort out how to use water heater both for gas.......and then with hook up....cheers

Ultraheat is space heater, Ultrastor is water heater. Hopefully  someone will help with your question as I had different controls when I had that set up.