What is this under the Lounge seat in my 99 Hymer B544 Classic

Hello Martin

I haven't seen or heard of anything like this before. The blue pipe is the same as the one used on gas welding sets blue for Oxygen. The valve is obviously an electrically operated solenoid which shuts of the gas. I wonder if that is just what it is, a device for shutting of the gas via a switch. It is definitely retrofitted. Do you have an LPG gas tank under the floor?

Spinner

I dont think its a changeover valve because it would have 3 hoses connected not 2, it could be a solenoid isolator valve though as it appears to only have 2 hoses, for this to be the case there would have to be a switch in the Hab area to operate it. I agree the hoses are past their use by date at 13 years old. I have heard of electric isolators on motorhomes but have never actually seen one.......maybe this is one of those mythical creatures

Are both the bottles in the outside locker connected? If so the only thing I can guess of it being is an electric valve that switches from either one bottle to another or connects both together when one bottle runs out, to me it looks to be retro fitted and not a standard fitment.
As Neil says they do recommend that gas hoses are changed very regularly.
However what I do with mine is I check them with soapy water annually, if there is a leak it bubbles up. I know that others would not like doing it this way but it works for me and is not meant as a recommendation to others.

I hope someone can identify it for you, it's not something I recognise.

One observation is that if those are low pressure lpg pipes they're knocking on a bit (2004)