Hot Water Tank Bypass

[Cynthia77]

I have a 1977 GMC Coachmen VIP. I’m trying to winterize the water lines and I can’t find the hot water tank bypass for this system.
There isn’t a valve behind the tank either.
Thanks everyone.

 

[Hutch]

The tank and system drain look like to be the two white taps in your third picture.

 

[otherclive]

I’d agree with Hutch as the two pipes appear to be going downwards. I had a van where it also had an external tap under the floor. Don’t know if it was OEM or an owner modification.