Where are the shut-off valves?

[PatLee]

I have a 2019 25' International FB twin. I previously owned a 2005 19' Int'l Bambi and winterizing it was simple, with all 3 valves seen and reached through one hole cut into the supporting bed board.
However, in my 25' Int'l FB twin, I found just one cut-out beneath the right twin bed that gives me a view of what I think is my hot water heater. I also see a yellow knob in there (i think that's what it is) (photo attached). Question: Is that the hot water shut-off valve that I should close once I empty the water from the hot water heater on the outside?
I have emptied the fresh water tank by opening the valve stem between the axles on the street side.
What other valves do I need to locate before I winterize (I use the pink antifreeze method).
I have looked through all of the literature that AS gave me when I bought her but the only diagrams provided were in the Owner's Manual and are of the electrical systems for 2019 ASs. There are NONE for the plumbing systems.
Thanks so much for any help here.
P.S. The second photo is the opening to the Atwood furnace unit.

[mpsgolf]

Hard to see in pic but if part of hot water heater plumbing it is probably your shutoff / winterization valve.

There shpuld be hot and cold drain valves at low point of plumbing. You also need to make sure water is out of your water pump.

There should be decent instructions for winterization in your owners manual. I have some I found on internet as well. Our local AS dealer sometimes has how-to classes.

[overlander63]

That yellow Tee handle visible in your photo is the one and only bypass valve on your water heater.

[pcskier]

Just one valve to turn on your trailer for water heater bypass...the yellow one you've found.

Look under your trailer to located your low point drains. Often one or two under the fresh water tank enclosure, that are valves on the outside. Then, any other plastic tubes sticking out below...there will be a corresponding valve on the inside, same location. Your manual should refer to these valves in the plumbing or winterizing chapters.

[PatLee]

Thank you!

[PatLee]

The owners' manual does not have any plumbing diagrams that point me to where the valves are - hence this posting.
I've left a VM with Airstream factory's technical support and will hopefully get a call back on where my valves are. Thanks.

[PatLee]

Called Airstream Warranty/tech support today and Mike was very helpful. The yellow knob is indeed the hot water shut-off valve; and in addition to the low point drain valve, there are 2 other valves (brass) in close vicinity to the low point. They also sent me the plumbing diagrams for 2019. Ask and thou shalt receive.
Thanks for responses.

[Dlaker]

I have a 2016 25-foot rear twin bed and the yellow hot water shut-off valve is under the right rear bed, as everyone indicated. Underneath the trailer and just behind the front wheel on the passenger side are the three valves you spoke to AS about. The single while plastic valve is the freshwater tank drain, and the side by side brass valves are the low-point hot and cold drain valves. All are critical in winterizing your TT. Attached are a couple of decent instruction documents on winterizing. It's easy. I blow out first and then also fill with antifreeze because I live in Minnesota - belts and suspenders

[PatLee]

Thank you so much!!